fix(plugins): a built-in select in the compact sheet keeps its action name

The shared control named every icon-only select by its value ("Speed: Fast"),
including in the compact sheet, where the row already shows the value. The sheet
row is named by its action again ("Select speed"), as before the shared renderer.

docs/plugins.md

@@ -644,6 +644,35 @@ Mounted surfaces and command invocations have shorter API lifetimes.
 Keep the client entry synchronous: return its cleanup function immediately and start asynchronous
 work inside it. See the maintained [composer pill example](../plugin-examples/local-plugin/client/main.tsx).
 
+## Contribute composer items
+
+`addComposerItem` mounts a plugin component in the agent, draft and New workspace composers. The
+public contract is the [composer items reference](../public-docs/plugins/reference.md#composer-items).
+
+The composer is two contexts, provided by two owners (`packages/app/src/composer/session.tsx`).
+`Composer` provides `ComposerInput` (prompt and attachments). `AgentControls` and
+`DraftAgentControls` provide `ComposerAgent` (provider, model, mode, thinking, options, metadata and
+their commands). `toPluginComposer` (`packages/app/src/plugins/composer-items/`) joins them into the
+`PluginComposer` an item reads, so a plugin cannot tell which composer a command reaches. Add a
+capability to `ComposerAgent` and both implementations; never branch on `context` in the model.
+
+Plugin `Toggle`, `Select` and `Action`, the thinking select and provider option controls all
+render through `ComposerControl` (`packages/app/src/composer/agent-controls/composer-control.tsx`),
+a toolbar icon or a row in the overflow sheet. Model and mode stay specialized but share its trigger,
+density and overflow. Plugin items count in the density presence in `layout.ts`, so a composer
+condenses to make room for them. A custom component renders wherever its item is placed, and an
+item that renders nothing still counts for density; there is no registration for either.
+
+A command runs against the owner's current state, not the render that built the callback. The
+draft's form (`openAgentForm`) and options (`openDraftOptions`) are plain stores for that reason,
+and `draftComposerAgent` rejects a provider the host does not offer or a model its loaded catalog
+does not list. `ComposerControl` owns the pending state and the error toast for callbacks that
+return a promise.
+
+The overflow sheet's content portals to the app root, away from the composer. Pass
+`useComposerSheetBridge()` as the sheet's `contextBridge`, or `useComposer()` returns nothing and
+the sheet draws no plugin rows.
+
 ## Contribute timeline items
 
 Timeline transformers and renderers are client contributions. The daemon's canonical rows and

packages/app/e2e/browser/plugin-composer-items.spec.ts

@@ -0,0 +1,12 @@
+import { test } from "../support/fixtures";
+import { withComposerControlsExample } from "../support/helpers/plugin-composer-items";
+
+test("a narrow composer's overflow sheet shows a plugin item's row", async ({ page }) => {
+  test.setTimeout(120_000);
+  await withComposerControlsExample(page, async (composer) => {
+    await composer.narrowTheWindow();
+    await composer.openAgentFeatures();
+    await composer.expectFeatureRow("Needs review");
+    await composer.expectFeatureRow("Insert checklist");
+  });
+});

packages/app/e2e/support/helpers/plugin-composer-items.ts

@@ -0,0 +1,59 @@
+import { expect, test, type Page } from "@playwright/test";
+import { gotoAppShell } from "./app";
+import { openAgentRoute } from "./mock-agent";
+import { connectNewWorkspaceDaemonClient } from "./new-workspace";
+import { copyPluginExample } from "./plugin-fixture";
+import { seedWorkspace } from "./seed-client";
+
+const PLUGIN_ID = "composer-controls-example";
+const NARROW = { width: 500, height: 800 };
+
+/** Runs `run` in an agent's composer with the composer-controls example installed. */
+export async function withComposerControlsExample(
+  page: Page,
+  run: (composer: {
+    narrowTheWindow(): Promise<void>;
+    openAgentFeatures(): Promise<void>;
+    expectFeatureRow(name: string): Promise<void>;
+  }) => Promise<void>,
+) {
+  const workspace = await seedWorkspace({
+    repoPrefix: "composer-items-",
+    title: "Composer items",
+  });
+  const agent = await workspace.client.createAgent({
+    provider: "mock",
+    cwd: workspace.repoPath,
+    workspaceId: workspace.workspaceId,
+    title: "Composer items agent",
+    model: "ten-second-stream",
+    modeId: "load-test",
+  });
+  const client = await connectNewWorkspaceDaemonClient({ ownProjects: false });
+  const previous = await client.getDaemonConfig();
+  const example = await copyPluginExample("composer-controls");
+  try {
+    await client.patchDaemonConfig({ pluginsEnabled: true });
+    await client.installDirectoryPlugin(example.directory);
+    await gotoAppShell(page);
+    await openAgentRoute(page, { workspaceId: workspace.workspaceId, agentId: agent.id });
+    await run({
+      narrowTheWindow: () =>
+        test.step("narrow the window until the composer folds its controls away", () =>
+          page.setViewportSize(NARROW)),
+      openAgentFeatures: () =>
+        test.step("open the agent features sheet", async () => {
+          await page.getByRole("button", { name: "Open agent features", exact: true }).click();
+        }),
+      expectFeatureRow: (name) =>
+        test.step(`the sheet has a row for "${name}"`, () =>
+          expect(page.getByRole("button", { name, exact: true })).toBeVisible()),
+    });
+  } finally {
+    await client.removePlugin(PLUGIN_ID);
+    await client.patchDaemonConfig({ pluginsEnabled: previous.config.pluginsEnabled });
+    await client.close();
+    await example.cleanup();
+    await workspace.cleanup();
+  }
+}

packages/app/src/agent-controls/draft-options-model.ts

@@ -14,6 +14,9 @@ import type {
  * - `remembered`: the provider's last-used control values.
  * - `edits`: toggles made in this draft.
  *
+ * An edit of `null` removes the key from every layer, the way a patch does on a running agent, so
+ * the provider's default applies again.
+ *
  * Choosing a provider by hand starts the options over; applying a profile replaces the provider
  * and the options in one step, so the provider change that follows does not clear them.
  */
@@ -47,6 +50,11 @@ export interface DraftOptionsModel {
 export function openDraftOptions(input: {
   provider: string | null;
   seed?: ProviderOptions;
+  /**
+   * The provider the draft's form has now. An edit belongs to it even before the screen has
+   * rendered the change, so `setOption` observes it first.
+   */
+  currentProvider?: () => string | null;
 }): DraftOptionsModel {
   let state: DraftOptionsState = {
     provider: input.provider,
@@ -64,6 +72,15 @@ export function openDraftOptions(input: {
     for (const listener of listeners) listener();
   }
 
+  function observeProvider(provider: string | null): void {
+    publish((current) => {
+      if (provider === current.provider) return current;
+      // The first provider a draft picks does not discard what it was opened with.
+      if (current.provider === null) return { ...current, provider };
+      return { ...current, provider, seed: {}, edits: {}, resolved: null };
+    });
+  }
+
   return {
     getState: () => state,
     subscribe: (listener) => {
@@ -72,13 +89,7 @@ export function openDraftOptions(input: {
         listeners.delete(listener);
       };
     },
-    observeProvider: (provider) =>
-      publish((current) => {
-        if (provider === current.provider) return current;
-        // The first provider a draft picks does not discard what it was opened with.
-        if (current.provider === null) return { ...current, provider };
-        return { ...current, provider, seed: {}, edits: {}, resolved: null };
-      }),
+    observeProvider,
     applyProfile: (profile) =>
       publish((current) => ({
         ...current,
@@ -88,12 +99,14 @@ export function openDraftOptions(input: {
         resolved: current.provider === profile.provider ? current.resolved : null,
       })),
     setRemembered: (remembered) => publish((current) => ({ ...current, remembered })),
-    setOption: (key, value) =>
+    setOption: (key, value) => {
+      if (input.currentProvider) observeProvider(input.currentProvider());
       publish((current) =>
         Object.is(current.edits[key], value)
           ? current
           : { ...current, edits: { ...current.edits, [key]: value } },
-      ),
+      );
+    },
     applyResolved: (resolved) => publish((current) => ({ ...current, resolved })),
   };
 }
@@ -109,10 +122,14 @@ export function ownDraftOptions(state: DraftOptionsState): ProviderOptions | und
       ([key]) => controlKeys.has(key) && !(key in state.seed),
     ),
   );
-  const own = { ...state.seed, ...remembered, ...state.edits };
+  const own = withoutRemovals({ ...state.seed, ...remembered, ...state.edits });
   return Object.keys(own).length > 0 ? own : undefined;
 }
 
+function withoutRemovals(options: ProviderOptions): ProviderOptions {
+  return Object.fromEntries(Object.entries(options).filter(([, value]) => value !== null));
+}
+
 export type DraftControlsRequest = Pick<
   AgentSessionConfig,
   "provider" | "cwd" | "modeId" | "model" | "thinkingOptionId" | "providerOptions"
@@ -163,6 +180,20 @@ export function viewDraftOptions(
     options:
       resolved.requestKey === current.requestKey
         ? resolved.options
-        : { ...resolved.options, ...state.edits },
+        : withoutRemovals({ ...resolved.options, ...state.edits }),
   };
 }
+
+const NO_OPTIONS: ProviderOptions = {};
+
+/**
+ * The options the draft will create with, for a plugin or a control to read: the daemon's answer
+ * for this provider when there is one, otherwise the draft's own layers, so an edit shows before
+ * the daemon has answered.
+ */
+export function shownDraftOptions(
+  state: DraftOptionsState,
+  current: { provider: string | null; requestKey: string },
+): ProviderOptions {
+  return viewDraftOptions(state, current)?.options ?? ownDraftOptions(state) ?? NO_OPTIONS;
+}

packages/app/src/composer/agent-controls/composer-control.browser.test.tsx

@@ -0,0 +1,175 @@
+import React from "react";
+import { cleanup, fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { Scan } from "lucide-react-native";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import type { AgentOptionControl } from "@getpaseo/protocol/agent-types";
+import type { ToastApi } from "@/components/toast-host";
+import { ToastApiProvider } from "@/contexts/toast-api-context";
+import { ComposerControls, type ComposerControlItem } from "./composer-control";
+import { useAgentControlItems } from "./control-items";
+import { resolveComposerControlPresentation } from "./layout";
+
+beforeEach(() => vi.stubGlobal("React", React));
+afterEach(cleanup);
+
+const base = { id: "x", title: "Context", icon: Scan };
+
+type RecordingToast = ToastApi & { error: ReturnType<typeof vi.fn> };
+
+function createToast(): RecordingToast {
+  return { error: vi.fn() } as unknown as RecordingToast;
+}
+
+function ignoreOpenChange() {}
+
+function Controls({
+  items,
+  surface,
+  toast,
+}: {
+  items: ComposerControlItem[];
+  surface: "toolbar" | "sheet";
+  toast: ToastApi;
+}) {
+  return (
+    <ToastApiProvider api={toast}>
+      <ComposerControls
+        items={items}
+        surface={surface}
+        openId={null}
+        onOpenIdChange={ignoreOpenChange}
+      />
+    </ToastApiProvider>
+  );
+}
+
+function renderControls(items: ComposerControlItem[], surface: "toolbar" | "sheet" = "toolbar") {
+  const toast = createToast();
+  render(<Controls items={items} surface={surface} toast={toast} />);
+  return toast;
+}
+
+describe("ComposerControls", () => {
+  it("shows a select's chosen label, or only its icon when asked", () => {
+    const select: ComposerControlItem = {
+      ...base,
+      type: "select",
+      value: "large",
+      choices: [
+        { value: "small", label: "Small" },
+        { value: "large", label: "Large" },
+      ],
+      onChange: () => undefined,
+    };
+    renderControls([select]);
+    expect(screen.getByRole("button", { name: "Context" }).textContent).toContain("Large");
+  });
+
+  it("names the choice on an icon-only select, without drawing it", () => {
+    renderControls([
+      {
+        ...base,
+        type: "select",
+        value: "large",
+        iconOnly: true,
+        choices: [{ value: "large", label: "Large" }],
+        onChange: () => undefined,
+      },
+    ]);
+    const trigger = screen.getByRole("button", { name: "Context: Large" });
+    expect(trigger.textContent).not.toContain("Large");
+  });
+
+  it("flips a toggle on press in the toolbar", () => {
+    const onChange = vi.fn();
+    renderControls([{ ...base, type: "toggle", value: true, onChange }]);
+    fireEvent.click(screen.getByRole("button", { name: "Context" }));
+    expect(onChange).toHaveBeenCalledWith(false);
+  });
+
+  it("lists a toggle as On or Off in the sheet", () => {
+    renderControls([{ ...base, type: "toggle", value: true, onChange: () => undefined }], "sheet");
+    expect(screen.getByRole("button", { name: "Context" }).textContent).toContain("On");
+  });
+
+  it("reports a failed command the way a built-in control does, and frees the control", async () => {
+    let reject: (error: Error) => void = () => undefined;
+    const onPress = vi.fn(
+      () =>
+        new Promise<void>((_resolve, rejectPromise) => {
+          reject = rejectPromise;
+        }),
+    );
+    const toast = renderControls([{ ...base, type: "action", onPress }]);
+    const button = screen.getByRole("button", { name: "Context" });
+
+    fireEvent.click(button);
+    // While the command is in flight the control cannot be pressed again.
+    await waitFor(() => expect(button.getAttribute("aria-disabled")).toBe("true"));
+    fireEvent.click(button);
+    expect(onPress).toHaveBeenCalledTimes(1);
+
+    reject(new Error("Unknown or unavailable provider: x"));
+    await waitFor(() =>
+      expect(toast.error).toHaveBeenCalledWith("Unknown or unavailable provider: x"),
+    );
+    await waitFor(() => expect(button.getAttribute("aria-disabled")).not.toBe("true"));
+  });
+
+  it("reports a command that throws before it returns", () => {
+    const toast = renderControls([
+      {
+        ...base,
+        type: "action",
+        onPress: () => {
+          throw new Error("No such control");
+        },
+      },
+    ]);
+    fireEvent.click(screen.getByRole("button", { name: "Context" }));
+    expect(toast.error).toHaveBeenCalledWith("No such control");
+  });
+});
+
+const FAST_ON = { fast_mode: true };
+
+describe("provider option controls", () => {
+  const fastMode: AgentOptionControl = {
+    type: "toggle",
+    key: "fast_mode",
+    label: "Fast",
+    defaultValue: false,
+  };
+  function OptionControls({
+    options,
+    onSetOption,
+  }: {
+    options: Record<string, unknown>;
+    onSetOption: (key: string, value: unknown) => void;
+  }) {
+    const optionControls = React.useMemo(
+      () => ({ controls: [fastMode], options, onSetOption }),
+      [onSetOption, options],
+    );
+    const items = useAgentControlItems({
+      surface: "toolbar",
+      presentation: resolveComposerControlPresentation("full"),
+      thinking: null,
+      optionControls,
+    });
+    return <Controls items={items.features} surface="toolbar" toast={TOAST} />;
+  }
+  const TOAST = createToast();
+
+  function recordWrites(writes: Array<[string, unknown]>) {
+    return (key: string, value: unknown) => void writes.push([key, value]);
+  }
+
+  it("write the toggled option from the agent's current options", () => {
+    const writes: Array<[string, unknown]> = [];
+    const onSetOption = recordWrites(writes);
+    render(<OptionControls options={FAST_ON} onSetOption={onSetOption} />);
+    fireEvent.click(screen.getByTestId("agent-feature-fast_mode"));
+    expect(writes).toEqual([["fast_mode", false]]);
+  });
+});

packages/app/src/composer/agent-controls/composer-control.tsx

@@ -0,0 +1,307 @@
+import {
+  createContext,
+  useCallback,
+  useContext,
+  useMemo,
+  useRef,
+  useState,
+  type ReactElement,
+} from "react";
+import type { TFunction } from "i18next";
+import { useTranslation } from "react-i18next";
+import { Text, View } from "react-native";
+import { StyleSheet } from "react-native-unistyles";
+import type { AgentControlIcon } from "@/agent-controls/icons";
+import type { SheetHeader } from "@/components/adaptive-modal-sheet";
+import { Combobox, type ComboboxOption } from "@/components/ui/combobox";
+import { Tooltip, TooltipContent, TooltipTrigger } from "@/components/ui/tooltip";
+import { AgentControlTrigger } from "@/composer/agent-controls/control";
+import { useToast } from "@/contexts/toast-api-context";
+import { toErrorMessage } from "@/utils/error-messages";
+
+interface ComposerControlBase {
+  id: string;
+  title: string;
+  icon: AgentControlIcon;
+  /** Tints the icon; muted when absent. */
+  highlight?: "blue" | "green" | "yellow";
+  /** Defaults to the title, or to "title: choice" on an icon-only select. */
+  tooltip?: string;
+  /** Defaults to the tooltip. */
+  accessibilityLabel?: string;
+  testID?: string;
+}
+
+export interface ComposerControlChoice {
+  value: string;
+  label: string;
+  description?: string;
+}
+
+/**
+ * One control in the composer's toolbar, drawn from data. Provider option controls, thinking and
+ * plugin controls all come through here, so each is an icon in the toolbar and a row in the sheet.
+ */
+export type ComposerControlItem =
+  | (ComposerControlBase & {
+      type: "toggle";
+      value: boolean;
+      onChange: (value: boolean) => void | Promise<void>;
+    })
+  | (ComposerControlBase & {
+      type: "select";
+      value: string | null;
+      choices: readonly ComposerControlChoice[];
+      onChange: (value: string) => void | Promise<void>;
+      /** The toolbar trigger shows only the icon. */
+      iconOnly?: boolean;
+      showCaret?: boolean;
+      searchable?: boolean;
+      desktopMinWidth?: number;
+      renderOption?: (args: {
+        option: ComboboxOption;
+        selected: boolean;
+        active: boolean;
+        onPress: () => void;
+      }) => ReactElement;
+    })
+  | (ComposerControlBase & {
+      type: "action";
+      onPress: () => void | Promise<void>;
+    });
+
+export type ComposerControlSurface = "toolbar" | "sheet";
+
+const ComposerControlSurfaceContext = createContext<ComposerControlSurface>("toolbar");
+export const ComposerControlSurfaceProvider = ComposerControlSurfaceContext.Provider;
+
+/** Where the control being drawn sits: the toolbar, or a row in the overflow sheet. */
+export function useComposerControlSurface(): ComposerControlSurface {
+  return useContext(ComposerControlSurfaceContext);
+}
+
+interface ComposerControlProps {
+  item: ComposerControlItem;
+  surface: ComposerControlSurface;
+  disabled?: boolean;
+  open: boolean;
+  onOpenChange: (open: boolean) => void;
+  /** Runs after a toolbar toggle or action, so the composer can take focus back. */
+  onActionComplete?: () => void;
+}
+
+interface ControlView {
+  options: ComboboxOption[];
+  /** The list's selected id. */
+  selectedId: string;
+  /** What the trigger shows beside the icon. */
+  value: string;
+  iconOnly: boolean;
+  tooltip: string;
+  /** Whether pressing the trigger opens a list instead of acting. */
+  opensList: boolean;
+}
+
+function describeControl(
+  item: ComposerControlItem,
+  surface: ComposerControlSurface,
+  t: TFunction,
+): ControlView {
+  const isSheet = surface === "sheet";
+  if (item.type === "action") {
+    return {
+      options: [],
+      selectedId: "",
+      value: "",
+      iconOnly: true,
+      tooltip: item.tooltip ?? item.title,
+      opensList: false,
+    };
+  }
+  if (item.type === "toggle") {
+    const label = item.value ? t("agentControls.features.on") : t("agentControls.features.off");
+    return {
+      options: [
+        { id: "true", label: t("agentControls.features.on") },
+        { id: "false", label: t("agentControls.features.off") },
+      ],
+      selectedId: String(item.value),
+      value: label,
+      iconOnly: true,
+      tooltip: item.tooltip ?? item.title,
+      opensList: isSheet,
+    };
+  }
+  const choiceLabel =
+    item.choices.find((choice) => choice.value === item.value)?.label ?? item.title;
+  const iconOnly = item.iconOnly === true;
+  return {
+    options: item.choices.map((choice) => ({
+      id: choice.value,
+      label: choice.label,
+      description: choice.description,
+    })),
+    selectedId: String(item.value ?? ""),
+    value: choiceLabel,
+    iconOnly,
+    // An icon-only trigger names its value; a sheet row shows the value, so it names the action.
+    tooltip: iconOnly && !isSheet ? `${item.title}: ${choiceLabel}` : (item.tooltip ?? item.title),
+    opensList: true,
+  };
+}
+
+export function ComposerControl({
+  item,
+  surface,
+  disabled = false,
+  open,
+  onOpenChange,
+  onActionComplete,
+}: ComposerControlProps) {
+  const { t } = useTranslation();
+  const anchorRef = useRef<View>(null);
+  const isSheet = surface === "sheet";
+  const sheetHeader = useMemo<SheetHeader>(() => ({ title: item.title }), [item.title]);
+  const view = useMemo(() => describeControl(item, surface, t), [item, surface, t]);
+
+  // A command that returns a promise keeps the control pending until it settles, and a failure
+  // reaches the user the way a built-in live control's does.
+  const toast = useToast();
+  const [pending, setPending] = useState(false);
+  const run = useCallback(
+    (invoke: () => void | Promise<void>) => {
+      try {
+        const result = invoke();
+        if (!result) return;
+        setPending(true);
+        result
+          .catch((error: unknown) => toast.error(toErrorMessage(error)))
+          .finally(() => setPending(false));
+      } catch (error) {
+        toast.error(toErrorMessage(error));
+      }
+    },
+    [toast],
+  );
+  const handlePress = useCallback(() => {
+    if (item.type === "toggle") run(() => item.onChange(!item.value));
+    else if (item.type === "action") run(item.onPress);
+    onActionComplete?.();
+  }, [item, onActionComplete, run]);
+  const handleOpenPress = useCallback(() => onOpenChange(!open), [onOpenChange, open]);
+  const handleSelect = useCallback(
+    (value: string) => {
+      if (item.type === "select") run(() => item.onChange(value));
+      else if (item.type === "toggle") run(() => item.onChange(value === "true"));
+    },
+    [item, run],
+  );
+
+  const select = item.type === "select" ? item : null;
+  const trigger = (
+    <AgentControlTrigger
+      ref={anchorRef}
+      icon={item.icon}
+      iconColor={item.highlight ? styles[item.highlight].color : undefined}
+      surface={surface}
+      label={item.title}
+      value={view.value}
+      showToolbarLabel={!view.iconOnly}
+      showCaret={select?.showCaret === true && !isSheet}
+      open={view.opensList && open}
+      disabled={disabled || pending}
+      onPress={view.opensList ? handleOpenPress : handlePress}
+      accessibilityLabel={item.accessibilityLabel ?? view.tooltip}
+      testID={item.testID}
+    />
+  );
+
+  return (
+    <>
+      {isSheet ? (
+        trigger
+      ) : (
+        <Tooltip delayDuration={0} enabledOnDesktop enabledOnMobile={false}>
+          <TooltipTrigger asChild triggerRefProp="ref">
+            {trigger}
+          </TooltipTrigger>
+          <TooltipContent side="top" align="center" offset={8}>
+            <Text style={styles.tooltipText}>{view.tooltip}</Text>
+          </TooltipContent>
+        </Tooltip>
+      )}
+      {view.opensList ? (
+        <Combobox
+          options={view.options}
+          value={view.selectedId}
+          onSelect={handleSelect}
+          open={open}
+          onOpenChange={onOpenChange}
+          anchorRef={anchorRef}
+          presentation={isSheet ? "push" : undefined}
+          desktopPlacement={isSheet ? undefined : "top-start"}
+          desktopMinWidth={select?.desktopMinWidth}
+          searchable={select ? select.searchable : false}
+          renderOption={select?.renderOption}
+          header={isSheet ? sheetHeader : undefined}
+        />
+      ) : null}
+    </>
+  );
+}
+
+interface ComposerControlsProps {
+  items: readonly ComposerControlItem[];
+  surface: ComposerControlSurface;
+  disabled?: boolean;
+  /** The id of the item whose list is open. */
+  openId: string | null;
+  onOpenIdChange: (id: string | null) => void;
+  onActionComplete?: () => void;
+}
+
+/** A row of Paseo-owned controls that share one open list at a time. */
+export function ComposerControls({
+  items,
+  onOpenIdChange,
+  openId,
+  ...rest
+}: ComposerControlsProps) {
+  return (
+    <>
+      {items.map((item) => (
+        <ComposerControlSlot
+          key={item.id}
+          item={item}
+          open={openId === item.id}
+          onOpenIdChange={onOpenIdChange}
+          {...rest}
+        />
+      ))}
+    </>
+  );
+}
+
+function ComposerControlSlot({
+  item,
+  open,
+  onOpenIdChange,
+  ...rest
+}: Omit<ComposerControlsProps, "items" | "openId"> & { item: ComposerControlItem; open: boolean }) {
+  const handleOpenChange = useCallback(
+    (next: boolean) => onOpenIdChange(next ? item.id : null),
+    [item.id, onOpenIdChange],
+  );
+  return <ComposerControl item={item} open={open} onOpenChange={handleOpenChange} {...rest} />;
+}
+
+const styles = StyleSheet.create((theme) => ({
+  blue: { color: theme.colors.palette.blue[400] },
+  green: { color: theme.colors.palette.green[400] },
+  yellow: { color: theme.colors.palette.yellow[400] },
+  tooltipText: {
+    color: theme.colors.foreground,
+    fontSize: theme.fontSize.base,
+    lineHeight: theme.fontSize.base * 1.4,
+  },
+}));

packages/app/src/composer/agent-controls/control-items.tsx

@@ -0,0 +1,165 @@
+import { useMemo } from "react";
+import type { TFunction } from "i18next";
+import { useTranslation } from "react-i18next";
+import { StyleSheet } from "react-native-unistyles";
+import type { AgentOptionControl, ProviderOptions } from "@getpaseo/protocol/agent-types";
+import { getAgentFeatureIcon, ThinkingIcon } from "@/agent-controls/icons";
+import {
+  getControlTooltip,
+  isControlActive,
+  readSelectOption,
+  readToggleOption,
+  type ComposerOptionControls,
+} from "@/agent-controls/option-controls";
+import { ComboboxItem, type ComboboxOption } from "@/components/ui/combobox";
+import {
+  type ComposerControlItem,
+  type ComposerControlSurface,
+} from "@/composer/agent-controls/composer-control";
+import type { ComposerControlPresentation } from "@/composer/agent-controls/layout";
+import { getAgentControlHintKey, getFeatureHighlightColor } from "@/composer/agent-controls/utils";
+
+const SEARCH_THRESHOLD = 6;
+
+function getFeatureHighlight(
+  control: AgentOptionControl,
+  options: ProviderOptions,
+): ComposerControlItem["highlight"] {
+  if (!isControlActive(control, options)) return undefined;
+  const color = getFeatureHighlightColor(control.key);
+  return color === "default" ? undefined : color;
+}
+
+function toFeatureItem(
+  control: AgentOptionControl,
+  optionControls: ComposerOptionControls,
+): ComposerControlItem {
+  const { options, onSetOption } = optionControls;
+  const base = {
+    id: `feature-${control.key}`,
+    title: control.label,
+    icon: getAgentFeatureIcon(control.icon),
+    highlight: getFeatureHighlight(control, options),
+    testID: `agent-feature-${control.key}`,
+  };
+  if (control.type === "toggle") {
+    return {
+      ...base,
+      type: "toggle",
+      tooltip: getControlTooltip(control),
+      value: readToggleOption(control, options),
+      onChange: (value) => onSetOption(control.key, value),
+    };
+  }
+  const iconOnly = control.desktopTrigger === "icon";
+  return {
+    ...base,
+    type: "select",
+    tooltip: getControlTooltip(control),
+    value: readSelectOption(control, options),
+    choices: control.choices,
+    iconOnly,
+    onChange: (value) => onSetOption(control.key, value),
+  };
+}
+
+interface ThinkingControl {
+  options: readonly { id: string; label: string }[];
+  selectedId: string | undefined;
+  onSelect: (id: string) => void;
+  /** The select's displayed label, falling back like the compact model sheet. */
+  displayLabel: string;
+}
+
+/** The thinking select and the option controls, as the data `ComposerControl` draws. */
+export function useAgentControlItems({
+  surface,
+  presentation,
+  thinking,
+  optionControls,
+}: {
+  surface: ComposerControlSurface;
+  presentation: ComposerControlPresentation;
+  thinking: ThinkingControl | null;
+  optionControls: ComposerOptionControls | undefined;
+}): { thinking: ComposerControlItem[]; features: ComposerControlItem[] } {
+  const { t } = useTranslation();
+
+  const thinkingItem = useMemo(
+    () => (thinking ? [toThinkingItem({ thinking, surface, presentation, t })] : []),
+    [presentation, surface, t, thinking],
+  );
+  const features = useMemo(
+    () =>
+      optionControls
+        ? optionControls.controls.map((control) => toFeatureItem(control, optionControls))
+        : [],
+    [optionControls],
+  );
+  return { thinking: thinkingItem, features };
+}
+
+function toThinkingItem({
+  thinking,
+  surface,
+  presentation,
+  t,
+}: {
+  thinking: ThinkingControl;
+  surface: ComposerControlSurface;
+  presentation: ComposerControlPresentation;
+  t: TFunction;
+}): ComposerControlItem {
+  const isSheet = surface === "sheet";
+  return {
+    id: "thinking",
+    type: "select",
+    title: t("agentControls.thinking.title"),
+    icon: ThinkingIcon,
+    tooltip: t(getAgentControlHintKey("thinking")),
+    accessibilityLabel: t("agentControls.thinking.selectWithValue", {
+      value: thinking.displayLabel,
+    }),
+    testID: isSheet ? "agent-controls-thinking" : "agent-thinking-selector",
+    value: thinking.options.some((option) => option.id === thinking.selectedId)
+      ? (thinking.selectedId ?? null)
+      : (thinking.options[0]?.id ?? null),
+    choices: thinking.options.map((option) => ({ value: option.id, label: option.label })),
+    onChange: thinking.onSelect,
+    iconOnly: !presentation.showThinkingLabel,
+    showCaret: presentation.showCarets,
+    searchable: !isSheet && thinking.options.length > SEARCH_THRESHOLD,
+    desktopMinWidth: 200,
+    renderOption: (args) => <ThinkingOption {...args} />,
+  };
+}
+
+function ThinkingOption({
+  option,
+  selected,
+  active,
+  onPress,
+}: {
+  option: ComboboxOption;
+  selected: boolean;
+  active: boolean;
+  onPress: () => void;
+}) {
+  const leadingSlot = useMemo(
+    () => <ThinkingIcon size={16} color={styles.thinkingIcon.color} />,
+    [],
+  );
+  return (
+    <ComboboxItem
+      label={option.label}
+      selected={selected}
+      active={active}
+      onPress={onPress}
+      leadingSlot={leadingSlot}
+    />
+  );
+}
+
+const styles = StyleSheet.create((theme) => ({
+  thinkingIcon: { color: theme.colors.foreground },
+}));

packages/app/src/composer/agent-controls/layout.test.ts

@@ -34,6 +34,7 @@ describe("composer control layout", () => {
       hasThinking: true,
       hasMode: true,
       features: [{ type: "toggle" as const }],
+      pluginItems: 0,
       fontScale: 1,
     };
 
@@ -95,6 +96,7 @@ describe("composer control layout", () => {
           hasThinking: true,
           hasMode: true,
           features: [{ type: "toggle" }],
+          pluginItems: 0,
           fontScale: 1,
         },
       }),
@@ -107,6 +109,7 @@ describe("composer control layout", () => {
           hasThinking: true,
           hasMode: true,
           features: [{ type: "toggle" }, { type: "select", label: "Tools" }],
+          pluginItems: 0,
           fontScale: 1,
         },
       }),
@@ -119,6 +122,7 @@ describe("composer control layout", () => {
           hasThinking: true,
           hasMode: true,
           features: [{ type: "toggle" }],
+          pluginItems: 0,
           fontScale: 1.25,
         },
       }),
@@ -133,6 +137,7 @@ describe("composer control layout", () => {
         hasModel: true,
         hasThinking: true,
         hasMode: true,
+        pluginItems: 0,
         fontScale: 1,
       },
     };
@@ -154,6 +159,34 @@ describe("composer control layout", () => {
     ).toBe("condensed");
   });
 
+  it("condenses to make room for plugin items and keeps them in the overflow", () => {
+    const base = {
+      availableWidth: 430,
+      currentDensity: "full" as const,
+      controls: {
+        hasModel: true,
+        hasThinking: true,
+        hasMode: true,
+        features: [],
+        fontScale: 1,
+      },
+    };
+
+    expect(
+      resolveComposerControlDensity({ ...base, controls: { ...base.controls, pluginItems: 0 } }),
+    ).toBe("full");
+    expect(
+      resolveComposerControlDensity({ ...base, controls: { ...base.controls, pluginItems: 2 } }),
+    ).toBe("condensed");
+    expect(
+      resolveComposerControlDensity({
+        ...base,
+        availableWidth: 250,
+        controls: { ...base.controls, pluginItems: 2 },
+      }),
+    ).toBe("tight");
+  });
+
   it("gives every toolbar control one shell and one platform glyph envelope", () => {
     expect(COMPOSER_TOOLBAR_GEOMETRY).toEqual({
       controlSize: 28,

packages/app/src/composer/agent-controls/layout.ts

@@ -5,6 +5,8 @@ export interface ComposerControlPresence {
   hasThinking: boolean;
   hasMode: boolean;
   features: readonly ComposerFeatureControlPresence[];
+  /** Plugin composer items. Each is budgeted like a select with a short label. */
+  pluginItems: number;
   fontScale: number;
 }
 
@@ -26,6 +28,7 @@ export const COMPOSER_TOOLBAR_GEOMETRY = {
 } as const;
 
 const DENSITY_HYSTERESIS = 12;
+const PLUGIN_ITEM_LABEL = "Plugin item";
 
 function normalizedFontScale(fontScale: number): number {
   return Number.isFinite(fontScale) ? Math.max(1, fontScale) : 1;
@@ -62,7 +65,9 @@ function resolveCondensedFloor(controls: ComposerControlPresence): number {
   if (controls.hasModel) widths.push(36 + 60 * fontScale);
   if (controls.hasThinking) widths.push(COMPOSER_TOOLBAR_GEOMETRY.controlSize);
   if (controls.hasMode) widths.push(36 + 96 * fontScale);
-  if (controls.features.length > 0) widths.push(COMPOSER_TOOLBAR_GEOMETRY.controlSize);
+  if (controls.features.length > 0 || controls.pluginItems > 0) {
+    widths.push(COMPOSER_TOOLBAR_GEOMETRY.controlSize);
+  }
   return sumControlWidths(widths);
 }
 
@@ -75,6 +80,11 @@ function resolveFullFloor(controls: ComposerControlPresence): number {
   for (const feature of controls.features) {
     widths.push(resolveFeatureControlWidth(feature, fontScale));
   }
+  for (let index = 0; index < controls.pluginItems; index++) {
+    widths.push(
+      resolveFeatureControlWidth({ type: "select", label: PLUGIN_ITEM_LABEL }, fontScale),
+    );
+  }
   return sumControlWidths(widths);
 }
 

packages/app/src/composer/agent-controls/mode.test.ts

@@ -25,15 +25,19 @@ describe("resolveAgentControlsMode", () => {
         onSelectMode: () => undefined,
         models: [],
         selectedModel: "",
-        onSelectModel: () => undefined,
+        onSelectModel: () => true,
         isModelLoading: false,
         modelSelectorProviders: [],
         isAllModelsLoading: false,
-        onSelectProviderAndModel: () => undefined,
+        onSelectProviderAndModel: () => true,
+        options: {},
+        onSetOption: () => undefined,
         thinkingOptions: [],
         selectedThinkingOptionId: "",
         onSelectThinkingOption: () => undefined,
         onApplyAgentProfile: () => undefined,
+        metadata: {},
+        onSetMetadata: () => undefined,
       }),
     ).toBe("draft");
   });

packages/app/src/composer/agent-controls/model-sheet.tsx

@@ -5,6 +5,7 @@ import { StyleSheet } from "react-native-unistyles";
 import type { AgentProvider } from "@getpaseo/protocol/agent-types";
 import type { AgentProfilePicker, AgentProfileSeed } from "@/agent-profiles";
 import { AdaptiveModalSheet } from "@/components/adaptive-modal-sheet";
+import type { ContextBridge } from "@/components/ui/isolated-bottom-sheet-modal";
 import { ComboboxTrigger } from "@/components/ui/combobox-trigger";
 import { useProviderIcon } from "@/components/provider-icons";
 import { ModelBrowser, useModelBrowser } from "@/components/model-browser";
@@ -43,6 +44,8 @@ interface CompactModelSheetProps {
   serverId?: string | null;
   glyphSize: number;
   canSwitchProvider: boolean;
+  /** Carries the composer's contexts into the sheets, which draw away from it. */
+  contextBridge?: ContextBridge | null;
   children: ReactNode;
 }
 
@@ -95,6 +98,7 @@ export function CompactModelSheet({
   serverId = null,
   glyphSize,
   canSwitchProvider,
+  contextBridge = null,
   children,
 }: CompactModelSheetProps) {
   const { t } = useTranslation();
@@ -299,6 +303,7 @@ export function CompactModelSheet({
         snapPoints={SNAP_POINTS}
         scrollable={false}
         contentStyle={styles.sheetBody}
+        contextBridge={contextBridge}
         testID="agent-controls-model-sheet"
       >
         <View
@@ -347,6 +352,7 @@ export function CompactModelSheet({
           scrollable={false}
           presentation="push"
           contentStyle={styles.sheetBody}
+          contextBridge={contextBridge}
           testID="agent-controls-model-browser-sheet"
         >
           <View

packages/app/src/composer/agent-controls/sheet-bridge.tsx

@@ -0,0 +1,43 @@
+import { useCallback } from "react";
+import { QueryClientProvider, useQueryClient } from "@tanstack/react-query";
+import type { ContextBridge } from "@/components/ui/isolated-bottom-sheet-modal";
+import { ComposerControlLayoutProvider, useComposerControlLayout } from "./layout-context";
+import {
+  ComposerAgentProvider,
+  ComposerInputProvider,
+  useComposerAgent,
+  useComposerInput,
+} from "@/composer/session";
+import { ToastApiProvider, useToast } from "@/contexts/toast-api-context";
+
+/**
+ * A phone's overflow draws in a sheet whose content lands at the app root, away from the
+ * composer. This carries across what a control in it reads from the composer: the agent and input
+ * a plugin's `useComposer()` sits on, the layout, and the toast and query client the controls use.
+ * Call it from inside the composer, outside any sheet.
+ */
+export function useComposerSheetBridge(): ContextBridge {
+  const layout = useComposerControlLayout();
+  const agent = useComposerAgent();
+  const input = useComposerInput();
+  const toast = useToast();
+  const queryClient = useQueryClient();
+  return useCallback<ContextBridge>(
+    (content) => (
+      <QueryClientProvider client={queryClient}>
+        <ToastApiProvider api={toast}>
+          <ComposerControlLayoutProvider value={layout}>
+            <ComposerAgentProvider value={agent}>
+              {input ? (
+                <ComposerInputProvider value={input}>{content}</ComposerInputProvider>
+              ) : (
+                content
+              )}
+            </ComposerAgentProvider>
+          </ComposerControlLayoutProvider>
+        </ToastApiProvider>
+      </QueryClientProvider>
+    ),
+    [agent, input, layout, queryClient, toast],
+  );
+}

packages/app/src/composer/draft/composer-agent.test.ts

@@ -0,0 +1,182 @@
+import { describe, expect, it } from "vitest";
+import type { AgentModelDefinition } from "@getpaseo/protocol/agent-types";
+import type { AgentProviderDefinition } from "@getpaseo/protocol/provider-manifest";
+import {
+  draftControlsRequest,
+  openDraftOptions,
+  shownDraftOptions,
+} from "@/agent-controls/draft-options-model";
+import { openAgentForm, type AgentFormCatalog } from "@/provider-selection/agent-form-store";
+import { draftComposerAgent } from "./composer-agent";
+
+function definition(id: string, modeId: string): AgentProviderDefinition {
+  return {
+    id,
+    label: id,
+    description: id,
+    defaultModeId: modeId,
+    modes: [{ id: modeId, label: modeId, icon: "ShieldCheck", colorTier: "safe" }],
+  };
+}
+
+function model(provider: string, id: string, isDefault = false): AgentModelDefinition {
+  return { provider, id, label: id, isDefault };
+}
+
+/** The host: two providers with catalogs, and one that is ready but lists no models. */
+const catalog: AgentFormCatalog = {
+  selectableProviders: new Map([
+    ["claude", definition("claude", "default")],
+    ["codex", definition("codex", "auto")],
+    ["opencode", definition("opencode", "build")],
+  ]),
+  models: new Map([
+    ["claude", [model("claude", "sonnet", true)]],
+    ["codex", [model("codex", "gpt-5.4", true), model("codex", "gpt-5.5")]],
+    ["opencode", []],
+  ]),
+  providerPreferences: () => undefined,
+};
+
+/** A draft composer on the real form and options models. */
+function openDraft(context: "draft" | "new-workspace") {
+  const form = openAgentForm(() => catalog);
+  const options = openDraftOptions({
+    provider: null,
+    currentProvider: () => form.getState().form.provider,
+  });
+  // The screen hands the options the provider the form reaches.
+  form.subscribe(() => options.observeProvider(form.getState().form.provider));
+  form.setProviderAndModel("claude", "");
+
+  function agent() {
+    const { form: current } = form.getState();
+    return draftComposerAgent({
+      context,
+      selectedProvider: current.provider,
+      selectedModel: current.model,
+      selectedMode: current.modeId,
+      thinking: current.thinkingOptionId || null,
+      isLocked: () => false,
+      options: shownDraftOptions(options.getState(), {
+        provider: current.provider,
+        requestKey: "",
+      }),
+      metadata: {},
+      onSelectProviderAndModel: form.setProviderAndModel,
+      onSelectModel: form.setModel,
+      onSelectMode: () => undefined,
+      onSelectThinkingOption: () => undefined,
+      onSetOption: options.setOption,
+      onSetMetadata: () => undefined,
+    });
+  }
+
+  /** What the daemon is asked to resolve for the agent this draft would create. */
+  function request() {
+    const { form: current } = form.getState();
+    return draftControlsRequest(options.getState(), {
+      provider: current.provider,
+      cwd: "/repo",
+      modeId: current.modeId,
+      modelId: current.model,
+    });
+  }
+
+  return { form, agent, request };
+}
+
+describe("a draft's options", () => {
+  it("belong to the provider the form has now, before the screen has rendered the change", () => {
+    const form = openAgentForm(() => catalog);
+    const options = openDraftOptions({
+      provider: null,
+      currentProvider: () => form.getState().form.provider,
+    });
+    // No subscription: the screen observes the provider in an effect, after the command ran.
+    form.setProviderAndModel("claude", "");
+    options.observeProvider("claude");
+    options.setOption("context", "1m");
+
+    form.setProviderAndModel("codex", "");
+    options.setOption("effort", "high");
+
+    expect(options.getState()).toMatchObject({ provider: "codex", edits: { effort: "high" } });
+  });
+});
+
+describe.each(["draft", "new-workspace"] as const)("the %s composer's agent", (context) => {
+  it("applies each awaited command before the next one runs", async () => {
+    const draft = openDraft(context);
+    // A plugin keeps the object it was handed across its awaits.
+    const retained = draft.agent();
+
+    await retained.setProvider("codex");
+    await retained.setModel("gpt-5.5");
+    await retained.setOptions({ context: "1m" });
+
+    const agent = draft.agent();
+    expect(agent).toMatchObject({
+      context,
+      provider: "codex",
+      model: "gpt-5.5",
+      options: { context: "1m" },
+    });
+    expect(draft.request()).toMatchObject({
+      provider: "codex",
+      model: "gpt-5.5",
+      providerOptions: { context: "1m" },
+    });
+  });
+
+  it("starts the options over when the provider is chosen by hand", async () => {
+    const draft = openDraft(context);
+    const retained = draft.agent();
+
+    await retained.setOptions({ context: "1m" });
+    expect(draft.agent().options).toEqual({ context: "1m" });
+    await retained.setProvider("codex");
+
+    expect(draft.agent().options).toEqual({});
+  });
+
+  it("creates with the provider's default again once a plugin resets an option", async () => {
+    const draft = openDraft(context);
+    const retained = draft.agent();
+
+    await retained.setOptions({ context: "1m", effort: "high" });
+    await retained.setOptions({ context: null });
+
+    expect(draft.agent().options).toEqual({ effort: "high" });
+    expect(draft.request()?.providerOptions).toEqual({ effort: "high" });
+
+    await retained.setOptions({ effort: null });
+
+    expect(draft.agent().options).toEqual({});
+    expect(draft.request()?.providerOptions).toBeUndefined();
+  });
+
+  it("rejects a provider the host cannot run and a model the catalog does not list", async () => {
+    const draft = openDraft(context);
+    const retained = draft.agent();
+
+    await expect(retained.setProvider("nope")).rejects.toThrow(
+      "Unknown or unavailable provider: nope",
+    );
+    expect(draft.agent().provider).toBe("claude");
+
+    await retained.setProvider("codex");
+    await expect(retained.setModel("missing")).rejects.toThrow("Unknown model: missing");
+    expect(draft.agent()).toMatchObject({ provider: "codex", model: "gpt-5.4" });
+  });
+
+  it("keeps a model id as given when the provider lists no catalog", async () => {
+    const draft = openDraft(context);
+    const retained = draft.agent();
+
+    await retained.setProvider("opencode");
+    await retained.setModel("anthropic/claude-x");
+
+    expect(draft.agent().model).toBe("anthropic/claude-x");
+  });
+});

packages/app/src/composer/draft/composer-agent.ts

@@ -0,0 +1,52 @@
+import type { ComposerAgent } from "@/composer/session";
+import type { DraftAgentControlsProps } from "@/composer/agent-controls";
+
+/**
+ * The agent a draft composer creates, as a plugin sees it. Its commands go to the form and the
+ * options model, which apply them as they run, so a plugin can `await` one and issue the next.
+ */
+export function draftComposerAgent(
+  props: Pick<
+    DraftAgentControlsProps,
+    | "context"
+    | "disabled"
+    | "selectedProvider"
+    | "selectedModel"
+    | "selectedMode"
+    | "options"
+    | "metadata"
+    | "onSelectProviderAndModel"
+    | "onSelectModel"
+    | "onSelectMode"
+    | "onSelectThinkingOption"
+    | "onSetOption"
+    | "onSetMetadata"
+  > & { thinking: string | null; isLocked: () => boolean },
+): ComposerAgent {
+  return {
+    context: props.context ?? "draft",
+    locked: props.disabled ?? false,
+    isLocked: props.isLocked,
+    provider: props.selectedProvider,
+    model: props.selectedModel || null,
+    mode: props.selectedMode || null,
+    thinking: props.thinking,
+    options: props.options,
+    metadata: props.metadata,
+    // An empty model id picks the provider's default model.
+    setProvider: async (provider) => {
+      if (!props.onSelectProviderAndModel(provider, "")) {
+        throw new Error(`Unknown or unavailable provider: ${provider}`);
+      }
+    },
+    setModel: async (modelId) => {
+      if (!props.onSelectModel(modelId)) throw new Error(`Unknown model: ${modelId}`);
+    },
+    setMode: async (modeId) => props.onSelectMode(modeId),
+    setThinking: async (thinkingOptionId) => props.onSelectThinkingOption(thinkingOptionId),
+    setOptions: async (patch) => {
+      for (const [key, value] of Object.entries(patch)) props.onSetOption(key, value);
+    },
+    setMetadata: async (patch) => props.onSetMetadata(patch),
+  };
+}

packages/app/src/composer/draft/input-draft-core.ts

@@ -1,3 +1,4 @@
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
 import type { UserComposerAttachment } from "@/attachments/types";
 import type { DraftAgentControlsProps } from "@/composer/agent-controls";
 import type { UseAgentFormStateResult } from "@/hooks/use-agent-form-state";
@@ -21,10 +22,25 @@ export function resolveDraftKey(input: {
 export function buildDraftAgentControls(input: {
   formState: UseAgentFormStateResult;
   optionControls?: DraftAgentControlsProps["optionControls"];
+  options: DraftAgentControlsProps["options"];
+  onSetOption: DraftAgentControlsProps["onSetOption"];
   onApplyAgentProfile: DraftAgentControlsProps["onApplyAgentProfile"];
   onDropdownClose?: DraftAgentControlsProps["onDropdownClose"];
+  context: NonNullable<DraftAgentControlsProps["context"]>;
+  metadata: Record<string, JsonValue>;
+  onSetMetadata: (patch: Record<string, JsonValue>) => void;
 }): DraftAgentControlsProps {
-  const { formState, optionControls, onApplyAgentProfile, onDropdownClose } = input;
+  const {
+    formState,
+    optionControls,
+    options,
+    onSetOption,
+    onApplyAgentProfile,
+    onDropdownClose,
+    context,
+    metadata,
+    onSetMetadata,
+  } = input;
   return {
     providerDefinitions: formState.providerDefinitions,
     selectedProvider: formState.selectedProvider,
@@ -43,11 +59,16 @@ export function buildDraftAgentControls(input: {
     onSelectThinkingOption: formState.setThinkingOptionFromUser,
     onApplyAgentProfile,
     optionControls,
+    options,
+    onSetOption,
     onDropdownClose,
     onModelSelectorOpen: formState.refetchProviderModelsIfStale,
     onRetryModelProvider: formState.refreshProviderModels,
     isRetryingModelProvider: formState.isProviderModelsRefreshing,
     modelSelectorServerId: formState.selectedServerId,
+    context,
+    metadata,
+    onSetMetadata,
   };
 }
 

packages/app/src/composer/draft/input-draft.ts

@@ -1,4 +1,5 @@
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
 import type { UserComposerAttachment } from "@/attachments/types";
 import type { TextReplacement } from "@/composer/types";
 import type { DraftAgentControlsProps } from "@/composer/agent-controls";
@@ -28,6 +29,8 @@ import { useShallow } from "zustand/shallow";
 import type { ComposerTextSource } from "@/composer/text-source";
 import { isWeb } from "@/constants/platform";
 
+const NO_METADATA: Record<string, JsonValue> = {};
+
 type AttachmentUpdater =
   | UserComposerAttachment[]
   | ((prev: UserComposerAttachment[]) => UserComposerAttachment[]);
@@ -36,6 +39,8 @@ interface AgentInputDraftComposerOptions {
   initialServerId: string | null;
   initialValues?: CreateAgentInitialValues;
   initialProviderOptions?: Record<string, unknown>;
+  /** Which composer a plugin's `useComposer()` reports. */
+  context?: "draft" | "new-workspace";
   isVisible?: boolean;
   lockedWorkingDir?: string;
 }
@@ -51,6 +56,8 @@ type DraftComposerState = UseAgentFormStateResult & {
   effectiveModelId: string;
   effectiveThinkingOptionId: string;
   providerOptions: Record<string, unknown> | undefined;
+  /** What plugins set on the agent this draft creates. */
+  metadata: Record<string, JsonValue>;
   agentControls: DraftAgentControlsProps;
   commandDraft: DraftCommandTarget;
 };
@@ -191,10 +198,18 @@ export function useAgentInputDraft(input: UseAgentInputDraftInput): AgentInputDr
     [saveDraft],
   );
 
+  const metadata = useDraftStore((state) => state.metadataByDraftKey[draftKey] ?? NO_METADATA);
+  const setMetadata = useCallback(
+    (patch: Record<string, JsonValue>) =>
+      useDraftStore.getState().patchDraftMetadata({ draftKey, patch }),
+    [draftKey],
+  );
+
   const clear = useCallback(
     (lifecycle: "sent" | "abandoned") => {
       textPublication.cancel();
       useDraftStore.getState().clearDraftInput({ draftKey, lifecycle });
+      if (lifecycle === "sent") useDraftStore.getState().clearDraftMetadata({ draftKey });
     },
     [draftKey, textPublication],
   );
@@ -276,10 +291,13 @@ export function useAgentInputDraft(input: UseAgentInputDraftInput): AgentInputDr
   const {
     optionControls: draftOptionControls,
     options: draftOptions,
+    shownOptions: draftShownOptions,
+    setOption: setDraftOption,
     applyProfile: applyProfileOptions,
   } = useDraftProviderOptions({
     serverId: formState.selectedServerId,
     provider: formState.selectedProvider,
+    getProvider: formState.getSelectedProvider,
     cwd: workingDir,
     modeId: formState.selectedMode,
     modelId: effectiveModelId,
@@ -319,10 +337,16 @@ export function useAgentInputDraft(input: UseAgentInputDraftInput): AgentInputDr
       effectiveModelId,
       effectiveThinkingOptionId,
       providerOptions: draftOptions,
+      metadata,
       agentControls: buildDraftAgentControls({
         formState,
         optionControls: draftOptionControls,
+        options: draftShownOptions,
+        onSetOption: setDraftOption,
         onApplyAgentProfile: applyDraftAgentProfile,
+        context: composerOptions.context ?? "draft",
+        metadata,
+        onSetMetadata: setMetadata,
       }),
       commandDraft,
     };
@@ -334,8 +358,12 @@ export function useAgentInputDraft(input: UseAgentInputDraftInput): AgentInputDr
     effectiveThinkingOptionId,
     draftOptionControls,
     draftOptions,
+    draftShownOptions,
+    setDraftOption,
     applyDraftAgentProfile,
     formState,
+    metadata,
+    setMetadata,
     workingDir,
   ]);
 

packages/app/src/composer/draft/metadata.test.ts

@@ -0,0 +1,19 @@
+import { describe, expect, it } from "vitest";
+import { applyMetadataPatch } from "./metadata";
+
+describe("applyMetadataPatch", () => {
+  it("replaces top-level keys and removes keys patched to null", () => {
+    expect(
+      applyMetadataPatch(
+        { "linear.issue": { id: "ENG-1" }, review: true },
+        { "linear.issue": { id: "ENG-2" }, review: null, extra: [1] },
+      ),
+    ).toEqual({ "linear.issue": { id: "ENG-2" }, extra: [1] });
+  });
+
+  it("leaves the current record untouched", () => {
+    const current = { review: true };
+    applyMetadataPatch(current, { review: null });
+    expect(current).toEqual({ review: true });
+  });
+});

packages/app/src/composer/draft/metadata.ts

@@ -0,0 +1,14 @@
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
+
+/** Top-level keys replace; `null` removes the key. The daemon applies the same rule to an agent. */
+export function applyMetadataPatch(
+  current: Readonly<Record<string, JsonValue>>,
+  patch: Readonly<Record<string, JsonValue>>,
+): Record<string, JsonValue> {
+  const next = { ...current };
+  for (const [key, value] of Object.entries(patch)) {
+    if (value === null) delete next[key];
+    else next[key] = value;
+  }
+  return next;
+}

packages/app/src/composer/draft/workspace-tab.tsx

@@ -1,5 +1,6 @@
 import type { ComposerOptionControls } from "@/agent-controls/option-controls";
 import { useCallback, useEffect, useMemo, useRef } from "react";
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
 import { Keyboard, ScrollView, StyleSheet as RNStyleSheet, Text, View } from "react-native";
 import { useTranslation } from "react-i18next";
 import { StyleSheet } from "react-native-unistyles";
@@ -133,6 +134,7 @@ async function submitDraftCreateRequest(input: {
     effectiveModelId: string | null;
     effectiveThinkingOptionId: string | null;
     providerOptions: Record<string, unknown> | undefined;
+    metadata: Record<string, JsonValue>;
   };
   hostDisconnectedMessage: string;
   selectModelMessage: string;
@@ -182,6 +184,7 @@ async function submitDraftCreateRequest(input: {
     workspaceId,
     initialPrompt: text,
     clientMessageId: attempt.clientMessageId,
+    ...(Object.keys(composerState.metadata).length > 0 ? { metadata: composerState.metadata } : {}),
     ...(imagesData && imagesData.length > 0 ? { images: imagesData } : {}),
     ...(attachmentsArray && attachmentsArray.length > 0 ? { attachments: attachmentsArray } : {}),
   };
@@ -510,7 +513,9 @@ export function WorkspaceDraftAgentTab({
         providers: composerState.modelSelectorProviders,
         selectedProvider: draftProvider,
         selectedModelId: composerState.effectiveModelId,
-        select: composerState.setProviderAndModelFromUser,
+        select: (provider, modelId) => {
+          composerState.setProviderAndModelFromUser(provider, modelId);
+        },
       },
       thinking: {
         options: draftThinkingOptions,

packages/app/src/composer/index.tsx

@@ -139,6 +139,8 @@ import type {
 } from "@/attachments/types";
 import type { SelectedFile } from "@/attachments/selected-file";
 import { resolveComposerAttachmentSubmitFormat } from "@/composer/attachments/submit";
+import { ComposerInputProvider, type ComposerInput } from "@/composer/session";
+import { insertAtSelection } from "@/composer/insert-text";
 import { composerWorkspaceAttachment } from "@/composer/attachments/workspace";
 import { useWorkspaceAttachmentsForScopes } from "@/attachments/workspace-attachments-store";
 import { droppedItemsToSelectedFiles } from "@/composer/attachments/drop";
@@ -1419,6 +1421,40 @@ function ComposerContentImpl({
     [onChangeText],
   );
 
+  const insertUserInput = useCallback(
+    (text: string) => {
+      const input = messageInputRef.current;
+      if (!input) {
+        onChangeText(textSource.getSnapshot() + text);
+        return;
+      }
+      const inserted = insertAtSelection(input.getInputSnapshot(), text);
+      input.replaceText(inserted.text, inserted.selection);
+    },
+    [onChangeText, textSource],
+  );
+  const isComposerLockedRef = useRef(isComposerLocked);
+  isComposerLockedRef.current = isComposerLocked;
+  const composerInput = useMemo<ComposerInput>(
+    () => ({
+      locked: isComposerLocked,
+      isLocked: () => isComposerLockedRef.current,
+      textSource,
+      setText: replaceUserInput,
+      insertText: insertUserInput,
+      attachments,
+      changeAttachments: setSelectedAttachments,
+    }),
+    [
+      attachments,
+      insertUserInput,
+      isComposerLocked,
+      replaceUserInput,
+      setSelectedAttachments,
+      textSource,
+    ],
+  );
+
   const runClientSlashCommand = useCallback(
     (command: ClientSlashCommand): boolean => {
       if (command.execution !== "immediate" || !onClientSlashCommand) {
@@ -2223,18 +2259,27 @@ function ComposerContentImpl({
     [attachments, setSelectedAttachments, setGithubSearchQuery, setIsGithubPickerOpen],
   );
 
-  const leftContent = useMemo(
-    () =>
-      renderLeftContent({
-        agentControls,
-        agentId,
-        serverId,
-        focusInput,
-        isCompactLayout,
-        showAgentControls: mode.showAgentControls,
-      }),
-    [agentControls, agentId, focusInput, isCompactLayout, mode.showAgentControls, serverId],
-  );
+  const leftContent = useMemo(() => {
+    const controls = renderLeftContent({
+      agentControls,
+      agentId,
+      serverId,
+      focusInput,
+      isCompactLayout,
+      showAgentControls: mode.showAgentControls,
+    });
+    return controls ? (
+      <ComposerInputProvider value={composerInput}>{controls}</ComposerInputProvider>
+    ) : null;
+  }, [
+    agentControls,
+    agentId,
+    composerInput,
+    focusInput,
+    isCompactLayout,
+    mode.showAgentControls,
+    serverId,
+  ]);
 
   const handleAttachButtonRef = useCallback((node: View | null) => {
     attachButtonRef.current = node;

packages/app/src/composer/insert-text.test.ts

@@ -0,0 +1,18 @@
+import { describe, expect, it } from "vitest";
+import { insertAtSelection } from "./insert-text";
+
+describe("insertAtSelection", () => {
+  it("inserts at the caret and moves the caret after the insertion", () => {
+    expect(insertAtSelection({ text: "ab", selection: { start: 1, end: 1 } }, "XY")).toEqual({
+      text: "aXYb",
+      selection: { start: 3, end: 3 },
+    });
+  });
+
+  it("replaces the selection, however it was dragged", () => {
+    expect(insertAtSelection({ text: "abcd", selection: { start: 3, end: 1 } }, "-")).toEqual({
+      text: "a-d",
+      selection: { start: 2, end: 2 },
+    });
+  });
+});

packages/app/src/composer/insert-text.ts

@@ -0,0 +1,15 @@
+import type { ComposerInputSnapshot } from "@/composer/input/input";
+
+/** The text with `inserted` in place of the selection, and the caret after it. */
+export function insertAtSelection(
+  { text, selection }: ComposerInputSnapshot,
+  inserted: string,
+): ComposerInputSnapshot {
+  const start = Math.min(selection.start, selection.end);
+  const end = Math.max(selection.start, selection.end);
+  const caret = start + inserted.length;
+  return {
+    text: text.slice(0, start) + inserted + text.slice(end),
+    selection: { start: caret, end: caret },
+  };
+}

packages/app/src/composer/session.tsx

@@ -0,0 +1,89 @@
+import { createContext, useContext, type ReactNode } from "react";
+import type { JsonValue, ProviderOptions } from "@getpaseo/protocol/agent-types";
+import type { UserComposerAttachment } from "@/attachments/types";
+import type { ComposerTextSource } from "@/composer/text-source";
+
+/**
+ * The text and attachments of the composer a control sits in. `Composer` provides it, so a
+ * control reaches the prompt without knowing which screen mounted the composer.
+ */
+export interface ComposerInput {
+  /** The prompt is held while the composer submits; the built-in input is read-only meanwhile. */
+  locked: boolean;
+  /** `locked` as it is now. A command a plugin kept from an earlier render asks this. */
+  isLocked: () => boolean;
+  textSource: ComposerTextSource;
+  setText: (text: string) => void;
+  /** Inserts at the cursor, replacing the selection. */
+  insertText: (text: string) => void;
+  attachments: readonly UserComposerAttachment[];
+  changeAttachments: (
+    updater: (current: UserComposerAttachment[]) => UserComposerAttachment[],
+  ) => void;
+}
+
+/**
+ * The agent a composer configures, as one set of reads and commands. A running agent sends each
+ * command to the daemon; a draft keeps it locally until the agent is created. Controls call the
+ * same command either way.
+ */
+export interface ComposerAgent {
+  context: "agent" | "draft" | "new-workspace";
+  /** The agent is being created; the built-in controls are disabled meanwhile. */
+  locked: boolean;
+  /** `locked` as it is now. A command a plugin kept from an earlier render asks this. */
+  isLocked: () => boolean;
+  provider: string | null;
+  model: string | null;
+  mode: string | null;
+  thinking: string | null;
+  /** The options the agent runs with, defaults included. */
+  options: ProviderOptions;
+  metadata: Record<string, JsonValue>;
+  setProvider: (provider: string) => Promise<void>;
+  setModel: (modelId: string) => Promise<void>;
+  setMode: (modeId: string) => Promise<void>;
+  setThinking: (thinkingOptionId: string) => Promise<void>;
+  /** Top-level keys replace; `null` removes the agent's own value. */
+  setOptions: (patch: ProviderOptions) => Promise<void>;
+  /** Top-level keys replace; `null` removes the key. */
+  setMetadata: (patch: Record<string, JsonValue>) => Promise<void>;
+}
+
+const ComposerInputContext = createContext<ComposerInput | null>(null);
+const ComposerAgentContext = createContext<ComposerAgent | null>(null);
+
+export function ComposerInputProvider({
+  value,
+  children,
+}: {
+  value: ComposerInput;
+  children: ReactNode;
+}) {
+  return <ComposerInputContext.Provider value={value}>{children}</ComposerInputContext.Provider>;
+}
+
+export function ComposerAgentProvider({
+  value,
+  children,
+}: {
+  value: ComposerAgent | null;
+  children: ReactNode;
+}) {
+  return <ComposerAgentContext.Provider value={value}>{children}</ComposerAgentContext.Provider>;
+}
+
+export function useComposerInput(): ComposerInput | null {
+  return useContext(ComposerInputContext);
+}
+
+export function useComposerAgent(): ComposerAgent | null {
+  return useContext(ComposerAgentContext);
+}
+
+/** True while the composer holds its prompt or its agent's settings for a submit in flight. */
+export function useComposerLocked(): boolean {
+  const input = useComposerInput();
+  const agent = useComposerAgent();
+  return Boolean(input?.locked || agent?.locked);
+}

packages/app/src/hooks/use-agent-form-state.ts

@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useMemo, useReducer, useRef } from "react";
+import { useCallback, useEffect, useMemo, useRef, useState, useSyncExternalStore } from "react";
 import type { AgentProviderDefinition } from "@getpaseo/protocol/provider-manifest";
 import type {
   AgentMode,
@@ -28,14 +28,13 @@ import {
   mergeSelectedComposerPreferences,
   buildProviderDefinitionMap,
   buildProviderDefinitionMapForStatuses,
-  INITIAL_AGENT_FORM_RESOLUTION,
-  INITIAL_USER_MODIFIED,
   RESOLVABLE_PROVIDER_STATUSES,
   SELECTABLE_PROVIDER_STATUSES,
   type FormInitialValues,
   type FormState,
   type ProviderModelsByProvider,
 } from "@/provider-selection/resolve-agent-form";
+import { openAgentForm, type AgentFormCatalog } from "@/provider-selection/agent-form-store";
 import { useHostRuntimeIsConnected } from "@/runtime/host-runtime";
 import type { MaterializedAgentProfile } from "@/agent-profiles";
 
@@ -52,10 +51,13 @@ export interface UseAgentFormStateOptions {
 export interface UseAgentFormStateResult {
   selectedServerId: string | null;
   selectedProvider: AgentProvider | null;
+  /** The provider as it is now, which a render may not have reached yet. */
+  getSelectedProvider: () => AgentProvider | null;
   selectedMode: string;
   setModeFromUser: (modeId: string) => void;
   selectedModel: string;
-  setModelFromUser: (modelId: string) => void;
+  /** `false` when the provider's loaded catalog does not list the model. */
+  setModelFromUser: (modelId: string) => boolean;
   selectedThinkingOptionId: string;
   setThinkingOptionFromUser: (thinkingOptionId: string) => void;
   workingDir: string;
@@ -74,13 +76,20 @@ export interface UseAgentFormStateResult {
   modelError: string | null;
   refreshProviderModels: (provider?: AgentProvider) => void;
   refetchProviderModelsIfStale: () => void;
-  setProviderAndModelFromUser: (provider: AgentProvider, modelId: string) => void;
+  /** `false` when the provider is unknown or not ready. */
+  setProviderAndModelFromUser: (provider: AgentProvider, modelId: string) => boolean;
   applyProfileFromUser: (profile: MaterializedAgentProfile) => void;
   clearProviderSelectionFromUser: () => void;
   workingDirIsEmpty: boolean;
   persistFormPreferences: () => Promise<void>;
 }
 
+const EMPTY_CATALOG: AgentFormCatalog = {
+  selectableProviders: new Map(),
+  models: new Map(),
+  providerPreferences: () => undefined,
+};
+
 function resolveSelectedProviderModes(input: {
   selectedEntry: ProviderSnapshotEntry | null;
   provider: AgentProvider | null;
@@ -172,11 +181,15 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
     [updatePreferences],
   );
 
-  const [{ form: formState, userModified, resolution }, dispatch] = useReducer(resolveAgentForm, {
-    form: { provider: null, modeId: "", model: "", thinkingOptionId: "" },
-    userModified: INITIAL_USER_MODIFIED,
-    resolution: INITIAL_AGENT_FORM_RESOLUTION,
-  });
+  // The store reads what the host offers when a command runs; each render publishes the latest.
+  const catalogRef = useRef<AgentFormCatalog>(EMPTY_CATALOG);
+  const [formStore] = useState(() => openAgentForm(() => catalogRef.current));
+  const { form: formState, resolution } = useSyncExternalStore(
+    formStore.subscribe,
+    formStore.getState,
+    formStore.getState,
+  );
+  const dispatch = formStore.dispatch;
 
   const {
     entries: snapshotEntries,
@@ -246,6 +259,12 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
   const providerDefinitionMap = snapshotProviderDefinitionMap;
   const selectableProviderDefinitionMap = snapshotSelectableProviderDefinitionMap;
   const allProviderModels = snapshotAllProviderModels;
+  catalogRef.current = {
+    selectableProviders: selectableProviderDefinitionMap,
+    models: allProviderModels,
+    providerPreferences: (provider) =>
+      preferenceOverlayRef.current.current().providerPreferences?.[provider],
+  };
   const modelSelectorProviders = snapshotModelSelectorProviders;
   const availableModels = snapshotSelectedProviderModels;
   const modeOptions = snapshotSelectedProviderModes;
@@ -277,27 +296,15 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
     preferences,
     snapshotProviderModelsByProvider,
     snapshotResolvableProviderDefinitionMap,
+    dispatch,
   ]);
 
   const setProviderAndModelFromUser = useCallback(
-    (provider: AgentProvider, modelId: string) => {
-      if (!selectableProviderDefinitionMap.has(provider)) {
-        return;
-      }
-      const providerDef = selectableProviderDefinitionMap.get(provider);
+    (provider: AgentProvider, modelId: string): boolean => {
+      if (!formStore.setProviderAndModel(provider, modelId)) return false;
       const providerModels = allProviderModels.get(provider) ?? null;
-      const providerPrefs = preferenceOverlayRef.current.current().providerPreferences?.[provider];
-      const normalizedModelId = normalizeSelectedModelId(modelId);
-      const nextModelId = normalizedModelId || resolveDefaultModelId(providerModels);
-
-      dispatch({
-        type: "SET_PROVIDER_AND_MODEL_FROM_USER",
-        provider,
-        modelId,
-        providerDef,
-        providerModels,
-        providerPrefs,
-      });
+      const nextModelId =
+        normalizeSelectedModelId(modelId) || resolveDefaultModelId(providerModels);
       void updateCurrentPreferences((current) =>
         mergeSelectedComposerPreferences({
           preferences: current,
@@ -307,13 +314,14 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
           },
         }),
       );
+      return true;
     },
-    [allProviderModels, selectableProviderDefinitionMap, updateCurrentPreferences],
+    [allProviderModels, formStore, updateCurrentPreferences],
   );
 
   const clearProviderSelectionFromUser = useCallback(() => {
     dispatch({ type: "CLEAR_PROVIDER_SELECTION_FROM_USER" });
-  }, []);
+  }, [dispatch]);
 
   const applyProfileFromUser = useCallback(
     (profile: MaterializedAgentProfile) => {
@@ -322,7 +330,8 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
         return;
       }
 
-      const previousProvider = formState.provider;
+      const formBefore = formStore.getState();
+      const previousProvider = formBefore.form.provider;
       const providerDef = selectableProviderDefinitionMap.get(provider);
       const providerModels = allProviderModels.get(provider) ?? null;
       const providerPrefs = preferenceOverlayRef.current.current().providerPreferences?.[provider];
@@ -336,7 +345,7 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
         providerModels,
         providerPrefs,
       };
-      const nextState = resolveAgentForm({ form: formState, userModified, resolution }, action);
+      const nextState = resolveAgentForm(formBefore, action);
       const previousProviderModeIds = previousProvider
         ? (providerDefinitionMap.get(previousProvider)?.modes.map((mode) => mode.id) ?? [])
         : [];
@@ -360,19 +369,18 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
     },
     [
       allProviderModels,
-      formState,
+      dispatch,
+      formStore,
       providerDefinitionMap,
-      resolution,
       selectableProviderDefinitionMap,
       updateCurrentPreferences,
-      userModified,
     ],
   );
 
   const setModeFromUser = useCallback(
     (modeId: string) => {
       dispatch({ type: "SET_MODE_FROM_USER", modeId });
-      const provider = formState.provider;
+      const { provider } = formStore.getState().form;
       if (provider) {
         void updateCurrentPreferences((current) =>
           mergeSelectedComposerPreferences({
@@ -385,24 +393,18 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
         );
       }
     },
-    [formState.provider, updateCurrentPreferences],
+    [dispatch, formStore, updateCurrentPreferences],
   );
 
   const setModelFromUser = useCallback(
-    (modelId: string) => {
-      const provider = formState.provider;
-      const providerPrefs = provider
-        ? preferenceOverlayRef.current.current().providerPreferences?.[provider]
-        : undefined;
-      dispatch({
-        type: "SET_MODEL_FROM_USER",
-        modelId,
-        availableModels,
-        providerPrefs,
-      });
+    (modelId: string): boolean => {
+      if (!formStore.setModel(modelId)) return false;
+      const { provider } = formStore.getState().form;
       if (provider) {
-        const normalizedModelId = normalizeSelectedModelId(modelId);
-        const nextModelId = normalizedModelId || resolveDefaultModelId(availableModels);
+        const listed = allProviderModels.get(provider);
+        const nextModelId =
+          normalizeSelectedModelId(modelId) ||
+          resolveDefaultModelId(listed?.length ? listed : null);
         void updateCurrentPreferences((current) =>
           mergeSelectedComposerPreferences({
             preferences: current,
@@ -413,14 +415,15 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
           }),
         );
       }
+      return true;
     },
-    [availableModels, formState.provider, updateCurrentPreferences],
+    [allProviderModels, formStore, updateCurrentPreferences],
   );
 
   const setThinkingOptionFromUser = useCallback(
     (thinkingOptionId: string) => {
       dispatch({ type: "SET_THINKING_OPTION_FROM_USER", thinkingOptionId });
-      const { provider, model: modelId } = formState;
+      const { provider, model: modelId } = formStore.getState().form;
       if (provider && modelId) {
         void updateCurrentPreferences((current) =>
           mergeSelectedComposerPreferences({
@@ -435,9 +438,11 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
         );
       }
     },
-    [formState, updateCurrentPreferences],
+    [dispatch, formStore, updateCurrentPreferences],
   );
 
+  const getSelectedProvider = useCallback(() => formStore.getState().form.provider, [formStore]);
+
   const refreshProviderModels = useCallback(
     (provider?: AgentProvider) => {
       void refreshSnapshot(provider ? [provider] : undefined);
@@ -479,6 +484,7 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
     () => ({
       selectedServerId: serverId,
       selectedProvider: formState.provider,
+      getSelectedProvider,
       selectedMode: formState.modeId,
       setModeFromUser,
       selectedModel: formState.model,
@@ -509,6 +515,7 @@ export function useAgentFormState(options: UseAgentFormStateOptions): UseAgentFo
     }),
     [
       serverId,
+      getSelectedProvider,
       formState.provider,
       formState.modeId,
       formState.model,

packages/app/src/hooks/use-draft-provider-options.ts

@@ -5,6 +5,7 @@ import {
   draftControlsRequest,
   openDraftOptions,
   ownDraftOptions,
+  shownDraftOptions,
   viewDraftOptions,
 } from "@/agent-controls/draft-options-model";
 import type { ComposerOptionControls } from "@/agent-controls/option-controls";
@@ -19,6 +20,8 @@ import { mergeProviderPreferences, useFormPreferences } from "./use-form-prefere
 export function useDraftProviderOptions(input: {
   serverId: string | null | undefined;
   provider: AgentProvider | null;
+  /** The form's provider as it is now, which a render may not have reached yet. */
+  getProvider: () => AgentProvider | null;
   cwd: string | null | undefined;
   modeId: string | null | undefined;
   modelId: string | null | undefined;
@@ -26,8 +29,19 @@ export function useDraftProviderOptions(input: {
   initialOptions?: ProviderOptions;
 }) {
   const { t } = useTranslation();
-  const { serverId, provider, cwd, modeId, modelId, thinkingOptionId, initialOptions } = input;
-  const [model] = useState(() => openDraftOptions({ provider, seed: initialOptions }));
+  const {
+    serverId,
+    provider,
+    getProvider,
+    cwd,
+    modeId,
+    modelId,
+    thinkingOptionId,
+    initialOptions,
+  } = input;
+  const [model] = useState(() =>
+    openDraftOptions({ provider, seed: initialOptions, currentProvider: getProvider }),
+  );
   const state = useSyncExternalStore(model.subscribe, model.getState, model.getState);
   const client = useHostRuntimeClient(serverId ?? "");
   const isConnected = useHostRuntimeIsConnected(serverId ?? "");
@@ -77,21 +91,23 @@ export function useDraftProviderOptions(input: {
     if (provider && data) model.applyResolved({ provider, requestKey, ...data });
   }, [data, model, provider, requestKey]);
 
+  // An edit belongs to the provider the form has now, even before the render that shows it.
   const setOption = useCallback(
     (key: string, value: unknown) => {
       model.setOption(key, value);
-      if (!provider) return;
-      void updatePreferences((current) =>
+      const current = getProvider();
+      if (!current) return;
+      void updatePreferences((stored) =>
         mergeProviderPreferences({
-          preferences: current,
-          provider,
+          preferences: stored,
+          provider: current,
           updates: { options: { [key]: value } },
         }),
       ).catch((error) => {
         console.warn("[useDraftProviderOptions] persist option preference failed", error);
       });
     },
-    [model, provider, updatePreferences],
+    [getProvider, model, updatePreferences],
   );
 
   const view = viewDraftOptions(state, { provider, requestKey });
@@ -105,5 +121,14 @@ export function useDraftProviderOptions(input: {
     [setOption, viewControls, viewOptions],
   );
 
-  return { optionControls, options: ownOptions, applyProfile: model.applyProfile };
+  // What the draft will create with, the plugin's own edits included, before the daemon answers.
+  const shownOptions = shownDraftOptions(state, { provider, requestKey });
+
+  return {
+    optionControls,
+    options: ownOptions,
+    shownOptions,
+    setOption,
+    applyProfile: model.applyProfile,
+  };
 }

packages/app/src/plugins/buttons/model.test.ts

@@ -23,6 +23,7 @@ function installation(): InstalledPlugin {
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/client-state/snapshots.test.ts

@@ -53,6 +53,7 @@ const agent: Agent = {
   attentionReason: "permission",
   parentAgentId: null,
   labels: { phase: "implementation" },
+  metadata: { "linear.issue": { id: "ENG-1" } },
 };
 
 describe("plugin context snapshots", () => {
@@ -107,12 +108,16 @@ describe("plugin context snapshots", () => {
       attentionReason: "permission",
       parentAgentId: null,
       labels: { phase: "implementation" },
+      metadata: { "linear.issue": { id: "ENG-1" } },
     });
     expect(snapshot.labels).not.toBe(agent.labels);
     expect(Object.isFrozen(snapshot)).toBe(true);
     expect(Object.isFrozen(snapshot.labels)).toBe(true);
     expect(Reflect.set(snapshot, "title", "Hostile rename")).toBe(false);
     expect(Reflect.set(snapshot.labels, "phase", "hostile")).toBe(false);
+    const issue = snapshot.metadata["linear.issue"] as { id: string };
+    expect(Reflect.set(issue, "id", "hostile")).toBe(false);
+    expect(agent.metadata?.["linear.issue"]).toEqual({ id: "ENG-1" });
     expect(snapshot.title).toBe("Implement plugin panels");
     expect(snapshot.labels).toEqual({ phase: "implementation" });
     expect(agent.title).toBe("Implement plugin panels");

packages/app/src/plugins/client-state/snapshots.ts

@@ -1,5 +1,6 @@
 import type { PluginAgentSnapshot, PluginWorkspaceSnapshot } from "@getpaseo/plugin";
 import type { Agent, WorkspaceDescriptor } from "@/stores/session-store";
+import { cloneAndFreeze } from "../freeze";
 
 const workspaceSnapshots = new WeakMap<WorkspaceDescriptor, PluginWorkspaceSnapshot>();
 const agentSnapshots = new WeakMap<Agent, Map<string, PluginAgentSnapshot>>();
@@ -49,6 +50,7 @@ export function createPluginAgentSnapshot(agent: Agent, workspaceId: string): Pl
     attentionReason: agent.attentionReason ?? null,
     parentAgentId: agent.parentAgentId,
     labels: Object.freeze({ ...agent.labels }),
+    metadata: cloneAndFreeze(agent.metadata ?? {}),
   });
   const byWorkspace = agentSnapshots.get(agent) ?? new Map<string, PluginAgentSnapshot>();
   byWorkspace.set(workspaceId, snapshot);

packages/app/src/plugins/command-center/contributions.test.ts

@@ -46,6 +46,7 @@ const agent: PluginAgentSnapshot = {
   attentionReason: null,
   parentAgentId: null,
   labels: {},
+  metadata: {},
 };
 
 const inspect = defineRpc({
@@ -82,6 +83,7 @@ function plugin(onAgentSelect: AgentCommandItem["onSelect"]): InstalledPlugin {
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [
       {
         id: "details",

packages/app/src/plugins/composer-items/index.tsx

@@ -0,0 +1,138 @@
+import { useMemo, useSyncExternalStore } from "react";
+import type { PluginHostProps } from "@getpaseo/plugin/client";
+import { PluginComposerProvider } from "@getpaseo/plugin/client/host";
+import { withUnistyles } from "react-native-unistyles";
+import {
+  ComposerControlSurfaceProvider,
+  type ComposerControlSurface,
+} from "@/composer/agent-controls/composer-control";
+import { useComposerAgent, useComposerInput } from "@/composer/session";
+import { useIsCompactFormFactor } from "@/constants/layout";
+import { useToast } from "@/contexts/toast-api-context";
+import { useHosts } from "@/runtime/host-runtime";
+import type { Theme } from "@/styles/theme";
+import { createPluginClientStateSource } from "../client-state/source";
+import { resolvePluginPlatform } from "../platform";
+import { PluginEnvironmentProvider, type PluginEnvironment } from "../popover";
+import { useInstalledPlugins } from "../registry";
+import { SurfaceErrorBoundary } from "../surface-error-boundary";
+import { toPluginTheme } from "../theme";
+import type { InstalledPlugin } from "../types";
+import { toPluginComposer } from "./model";
+
+const pluginThemeMapping = (theme: Theme) => ({ theme: toPluginTheme(theme) });
+
+function renderNothing() {
+  return null;
+}
+
+function useServerPlugins(serverId: string | null): InstalledPlugin[] {
+  const installed = useInstalledPlugins();
+  return useMemo(
+    () =>
+      serverId === null
+        ? []
+        : installed.filter(
+            (plugin) => plugin.serverId === serverId && plugin.composerItems.length > 0,
+          ),
+    [installed, serverId],
+  );
+}
+
+/** How many composer items the host's plugins registered; the toolbar budgets room for them. */
+export function usePluginComposerItemCount(serverId: string | null): number {
+  const plugins = useServerPlugins(serverId);
+  return plugins.reduce((count, plugin) => count + plugin.composerItems.length, 0);
+}
+
+/**
+ * The host's plugin composer items. They read and command the composer they are mounted in, so
+ * they render only where a composer provides its input and agent.
+ */
+export function PluginComposerItems({
+  serverId,
+  surface,
+}: {
+  serverId: string | null;
+  surface: ComposerControlSurface;
+}) {
+  const plugins = useServerPlugins(serverId);
+  if (serverId === null || plugins.length === 0) return null;
+  return (
+    <ComposerControlSurfaceProvider value={surface}>
+      {plugins.map((plugin) => (
+        <ThemedPluginComposerItems key={plugin.id} plugin={plugin} uniProps={pluginThemeMapping} />
+      ))}
+    </ComposerControlSurfaceProvider>
+  );
+}
+
+function PluginComposerItemsHost({
+  plugin,
+  theme,
+}: {
+  plugin: InstalledPlugin;
+  theme: PluginHostProps["theme"];
+}) {
+  const agent = useComposerAgent();
+  const composerInput = useComposerInput();
+  const toast = useToast();
+  const compact = useIsCompactFormFactor();
+  const hosts = useHosts();
+  const hostLabel =
+    hosts.find((host) => host.serverId === plugin.serverId)?.label ?? plugin.serverId;
+  const textSource = composerInput?.textSource;
+  const prompt = useSyncExternalStore(
+    textSource?.subscribe ?? subscribeNothing,
+    textSource?.getSnapshot ?? emptyText,
+    textSource?.getSnapshot ?? emptyText,
+  );
+  const environment = useMemo<PluginEnvironment>(
+    () => ({
+      installation: plugin,
+      toast,
+      state: createPluginClientStateSource(plugin.serverId),
+    }),
+    [plugin, toast],
+  );
+  const composer = useMemo(
+    () =>
+      agent && composerInput ? toPluginComposer({ plugin, agent, composerInput, prompt }) : null,
+    [agent, composerInput, plugin, prompt],
+  );
+  const props = useMemo<PluginHostProps>(
+    () => ({
+      theme,
+      host: { id: plugin.serverId, label: hostLabel },
+      layout: { compact, platform: resolvePluginPlatform() },
+    }),
+    [compact, hostLabel, plugin.serverId, theme],
+  );
+  if (!composer) return null;
+  return (
+    <PluginEnvironmentProvider environment={environment}>
+      <PluginComposerProvider composer={composer}>
+        {plugin.composerItems.map(({ id, Component }) => (
+          <SurfaceErrorBoundary
+            key={id}
+            installation={plugin}
+            Surface={Component}
+            renderError={renderNothing}
+          >
+            <Component {...props} />
+          </SurfaceErrorBoundary>
+        ))}
+      </PluginComposerProvider>
+    </PluginEnvironmentProvider>
+  );
+}
+
+const ThemedPluginComposerItems = withUnistyles(PluginComposerItemsHost);
+
+function subscribeNothing() {
+  return () => undefined;
+}
+
+function emptyText() {
+  return "";
+}

packages/app/src/plugins/composer-items/model.test.ts

@@ -0,0 +1,311 @@
+import { defineRpc } from "@getpaseo/plugin";
+import { PluginTranslationRuntime } from "@getpaseo/plugin/client/host";
+import { QueryClient } from "@tanstack/react-query";
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
+import { z } from "zod";
+import { describe, expect, it } from "vitest";
+import type { UserComposerAttachment } from "@/attachments/types";
+import type { ComposerAgent, ComposerInput } from "@/composer/session";
+import type { InstalledPlugin } from "../types";
+import { toPluginComposer } from "./model";
+
+function installed(): InstalledPlugin {
+  return {
+    id: "review",
+    serverId: "host-1",
+    clientBundle: "bundle",
+    lifetime: new AbortController(),
+    locale: "en",
+    i18n: new PluginTranslationRuntime({ getLocale: () => "en", subscribe: () => () => {} }),
+    queryClient: new QueryClient(),
+    paseo: {} as InstalledPlugin["paseo"],
+    invoke: async () => undefined,
+    cleanup: () => {},
+    settingsScreens: [],
+    surfaces: [],
+    sidebarItems: { header: [], footer: [] },
+    legacySidebarItems: [],
+    filePanels: [],
+    composerItems: [],
+    workspacePanels: [],
+    commandCenterItems: [],
+    clientSlashCommands: [],
+    attachmentSources: [
+      {
+        id: "issues",
+        title: "Issues",
+        pickerTitle: "Issues",
+        searchPlaceholder: "Search issues",
+        icon: "Bug",
+        search: defineRpc({
+          name: "issues.search",
+          input: z.object({}),
+          output: z.array(z.object({})),
+        }),
+      },
+    ],
+    themes: [],
+    timelineTransformers: [],
+    timelineRenderers: [],
+  };
+}
+
+const issue = {
+  id: "ISS-1",
+  identifier: "ISS-1",
+  title: "Fix it",
+  url: "https://example.com/ISS-1",
+  text: "Fix it",
+  resourceType: "issue",
+};
+
+function fakeAgent(context: ComposerAgent["context"], locked = false) {
+  const calls: string[] = [];
+  const agent: ComposerAgent = {
+    context,
+    locked,
+    isLocked: () => locked,
+    provider: "claude",
+    model: "sonnet",
+    mode: "default",
+    thinking: null,
+    options: { effort: "high" },
+    metadata: { flag: true },
+    // A running agent keeps its provider, as the real adapter does.
+    setProvider: async (provider) => {
+      if (context === "agent") throw new Error("A running agent cannot change provider.");
+      calls.push(`provider:${provider}`);
+    },
+    setModel: async (model) => void calls.push(`model:${model}`),
+    setMode: async (mode) => void calls.push(`mode:${mode}`),
+    setThinking: async (thinking) => void calls.push(`thinking:${thinking}`),
+    setOptions: async (patch) => void calls.push(`options:${JSON.stringify(patch)}`),
+    setMetadata: async (patch: Record<string, JsonValue>) =>
+      void calls.push(`metadata:${JSON.stringify(patch)}`),
+  };
+  return { agent, calls };
+}
+
+function fakeInput(initial: UserComposerAttachment[] = [], locked = false) {
+  const state = { text: "", attachments: initial };
+  const input: ComposerInput = {
+    locked,
+    isLocked: () => locked,
+    textSource: { getSnapshot: () => state.text, subscribe: () => () => {} },
+    setText: (text) => {
+      state.text = text;
+    },
+    insertText: (text) => {
+      state.text += text;
+    },
+    get attachments() {
+      return state.attachments;
+    },
+    changeAttachments: (updater) => {
+      state.attachments = updater(state.attachments);
+    },
+  };
+  return { input, state };
+}
+
+describe("toPluginComposer", () => {
+  it("reads the agent the composer configures and the context it sits in", () => {
+    const { agent } = fakeAgent("new-workspace");
+    const { input } = fakeInput();
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "hello",
+    });
+    expect(composer.context).toBe("new-workspace");
+    expect(composer.prompt).toBe("hello");
+    expect(composer.agent).toEqual({
+      provider: "claude",
+      model: "sonnet",
+      mode: "default",
+      thinking: null,
+      options: { effort: "high" },
+      metadata: { flag: true },
+    });
+  });
+
+  it.each(["agent", "draft"] as const)(
+    "sends every command to the %s composer's agent",
+    async (context) => {
+      const { agent, calls } = fakeAgent(context);
+      const { input } = fakeInput();
+      const composer = toPluginComposer({
+        plugin: installed(),
+        agent,
+        composerInput: input,
+        prompt: "",
+      });
+      await composer.setModel("gpt");
+      await composer.setMode("plan");
+      await composer.setThinking("high");
+      await composer.setOptions({ effort: "low" });
+      await composer.setMetadata({ flag: null });
+      expect(calls).toEqual([
+        "model:gpt",
+        "mode:plan",
+        "thinking:high",
+        'options:{"effort":"low"}',
+        'metadata:{"flag":null}',
+      ]);
+    },
+  );
+
+  it("lets a draft change provider and tells a running agent it cannot", async () => {
+    const { input } = fakeInput();
+    const draft = fakeAgent("draft");
+    await toPluginComposer({
+      plugin: installed(),
+      agent: draft.agent,
+      composerInput: input,
+      prompt: "",
+    }).setProvider("codex");
+    expect(draft.calls).toEqual(["provider:codex"]);
+
+    const running = fakeAgent("agent");
+    await expect(
+      toPluginComposer({
+        plugin: installed(),
+        agent: running.agent,
+        composerInput: input,
+        prompt: "",
+      }).setProvider("codex"),
+    ).rejects.toThrow("A running agent cannot change provider.");
+    expect(running.calls).toEqual([]);
+  });
+
+  it("changes the prompt and inserts at the cursor", () => {
+    const { agent } = fakeAgent("draft");
+    const { input, state } = fakeInput();
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+    composer.setPrompt("a");
+    composer.insertText("b");
+    expect(state.text).toBe("ab");
+  });
+
+  it("refuses every prompt and agent command while the composer is locked", async () => {
+    const { agent, calls } = fakeAgent("new-workspace", true);
+    const { input, state } = fakeInput([], true);
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+
+    expect(() => composer.setPrompt("a")).toThrow("The composer is locked");
+    expect(() => composer.insertText("b")).toThrow("The composer is locked");
+    expect(() => composer.addAttachment({ sourceId: "issues", item: issue })).toThrow(
+      "The composer is locked",
+    );
+    await expect(composer.setProvider("codex")).rejects.toThrow("The composer is locked");
+    await expect(composer.setModel("gpt")).rejects.toThrow("The composer is locked");
+    await expect(composer.setMode("plan")).rejects.toThrow("The composer is locked");
+    await expect(composer.setThinking("high")).rejects.toThrow("The composer is locked");
+    await expect(composer.setOptions({ effort: "low" })).rejects.toThrow("The composer is locked");
+    await expect(composer.setMetadata({ flag: null })).rejects.toThrow("The composer is locked");
+    expect(state.text).toBe("");
+    expect(calls).toEqual([]);
+  });
+
+  it("refuses a command a plugin kept from before the composer locked", async () => {
+    const { agent } = fakeAgent("new-workspace");
+    const { input } = fakeInput();
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+
+    // The plugin's action was awaiting an RPC when the user submitted.
+    const lock = { locked: true };
+    agent.isLocked = () => lock.locked;
+    input.isLocked = () => lock.locked;
+
+    expect(() => composer.insertText("late")).toThrow("The composer is locked");
+    expect(() => composer.addAttachment({ sourceId: "issues", item: issue })).toThrow(
+      "The composer is locked",
+    );
+    expect(() => composer.removeAttachment({ sourceId: "issues", itemId: issue.id })).toThrow(
+      "The composer is locked",
+    );
+    await expect(composer.setOptions({ effort: "low" })).rejects.toThrow("The composer is locked");
+  });
+
+  it("hands out options and metadata a plugin cannot change", () => {
+    const { agent } = fakeAgent("draft");
+    agent.metadata = { nested: { list: [1] } };
+    const { input } = fakeInput();
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+
+    expect(Object.isFrozen(composer.agent.options)).toBe(true);
+    expect(Object.isFrozen(composer.agent.metadata)).toBe(true);
+    expect(Object.isFrozen((composer.agent.metadata as { nested: object }).nested)).toBe(true);
+    expect(agent.metadata).toEqual({ nested: { list: [1] } });
+    expect(Object.isFrozen(agent.metadata)).toBe(false);
+  });
+
+  it("adds and removes the plugin's own attachments only", () => {
+    const { agent } = fakeAgent("agent");
+    const other: UserComposerAttachment = {
+      kind: "plugin_resource",
+      pluginId: "other",
+      sourceId: "issues",
+      sourceTitle: "Issues",
+      sourceIcon: "Bug",
+      item: issue,
+    };
+    const { input, state } = fakeInput([other]);
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+
+    composer.addAttachment({ sourceId: "issues", item: issue });
+    composer.addAttachment({ sourceId: "issues", item: issue });
+    expect(state.attachments).toHaveLength(2);
+
+    const next = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+    expect(next.attachments).toEqual([{ sourceId: "issues", item: issue }]);
+
+    composer.removeAttachment({ sourceId: "issues", itemId: "ISS-1" });
+    expect(state.attachments).toEqual([other]);
+  });
+
+  it("rejects an attachment from a source the plugin did not register", () => {
+    const { agent } = fakeAgent("agent");
+    const { input } = fakeInput();
+    const composer = toPluginComposer({
+      plugin: installed(),
+      agent,
+      composerInput: input,
+      prompt: "",
+    });
+    expect(() => composer.addAttachment({ sourceId: "nope", item: issue })).toThrow(
+      "Unknown attachment source: nope",
+    );
+  });
+});

packages/app/src/plugins/composer-items/model.ts

@@ -0,0 +1,103 @@
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
+import type { PluginComposer } from "@getpaseo/plugin/client";
+import type { UserComposerAttachment } from "@/attachments/types";
+import type { ComposerAgent, ComposerInput } from "@/composer/session";
+import type { InstalledPlugin } from "../types";
+import { createPluginResourceAttachment } from "../attachments/model";
+import { cloneAndFreeze } from "../freeze";
+
+function isPluginAttachment(
+  attachment: UserComposerAttachment,
+  pluginId: string,
+  sourceId: string,
+  itemId?: string,
+): boolean {
+  return (
+    attachment.kind === "plugin_resource" &&
+    attachment.pluginId === pluginId &&
+    attachment.sourceId === sourceId &&
+    (itemId === undefined || attachment.item.id === itemId)
+  );
+}
+
+const LOCKED_MESSAGE = "The composer is locked while the agent is being created.";
+
+function assertUnlocked(isLocked: () => boolean): void {
+  if (isLocked()) throw new Error(LOCKED_MESSAGE);
+}
+
+async function whenUnlocked(agent: ComposerAgent, command: () => Promise<void>): Promise<void> {
+  assertUnlocked(agent.isLocked);
+  await command();
+}
+
+/**
+ * What a plugin sees of the composer it sits in. `agent` and `input` are the composer's own
+ * halves, so the plugin's commands reach the same models the built-in controls use.
+ */
+export function toPluginComposer(input: {
+  plugin: InstalledPlugin;
+  agent: ComposerAgent;
+  composerInput: ComposerInput;
+  prompt: string;
+}): PluginComposer {
+  const { plugin, agent, composerInput, prompt } = input;
+  return {
+    context: agent.context,
+    prompt,
+    attachments: composerInput.attachments.flatMap((attachment) =>
+      attachment.kind === "plugin_resource" && attachment.pluginId === plugin.id
+        ? [{ sourceId: attachment.sourceId, item: attachment.item }]
+        : [],
+    ),
+    // Provider options are JSON on the wire.
+    agent: {
+      provider: agent.provider,
+      model: agent.model,
+      mode: agent.mode,
+      thinking: agent.thinking,
+      options: cloneAndFreeze(agent.options as Record<string, JsonValue>),
+      metadata: cloneAndFreeze(agent.metadata),
+    },
+    setPrompt: (text) => {
+      assertUnlocked(composerInput.isLocked);
+      composerInput.setText(text);
+    },
+    insertText: (text) => {
+      assertUnlocked(composerInput.isLocked);
+      composerInput.insertText(text);
+    },
+    addAttachment({ sourceId, item }) {
+      assertUnlocked(composerInput.isLocked);
+      const source = plugin.attachmentSources.find((candidate) => candidate.id === sourceId);
+      if (!source) throw new Error(`Unknown attachment source: ${sourceId}`);
+      const attachment = createPluginResourceAttachment(
+        {
+          pluginId: plugin.id,
+          sourceId,
+          sourceTitle: plugin.i18n.resolve(source.title, plugin.locale),
+          sourceIcon: source.icon,
+        },
+        item,
+      );
+      composerInput.changeAttachments((current) =>
+        current.some((candidate) => isPluginAttachment(candidate, plugin.id, sourceId, item.id))
+          ? current
+          : [...current, attachment],
+      );
+    },
+    removeAttachment({ sourceId, itemId }) {
+      assertUnlocked(composerInput.isLocked);
+      composerInput.changeAttachments((current) =>
+        current.filter((candidate) => !isPluginAttachment(candidate, plugin.id, sourceId, itemId)),
+      );
+    },
+    setProvider: (provider) => whenUnlocked(agent, () => agent.setProvider(provider)),
+    setModel: (modelId) => whenUnlocked(agent, () => agent.setModel(modelId)),
+    setMode: (modeId) => whenUnlocked(agent, () => agent.setMode(modeId)),
+    setThinking: (thinkingOptionId) =>
+      whenUnlocked(agent, () => agent.setThinking(thinkingOptionId)),
+    setOptions: (patch) => whenUnlocked(agent, () => agent.setOptions(patch)),
+    setMetadata: (patch) => whenUnlocked(agent, () => agent.setMetadata(patch)),
+  };
+}

packages/app/src/plugins/evaluate.test.ts

@@ -531,6 +531,38 @@ describe("evaluatePluginClientBundle", () => {
     ).toThrow("Duplicate Command Center item: review");
   });
 
+  it("collects composer items and releases an id on removal", () => {
+    const plugin = evaluatePluginClientBundle(
+      "review",
+      bundle(`
+        function Item() { return null; }
+        const remove = plugin.addComposerItem({ id: "flag", Component: Item });
+        remove();
+        plugin.addComposerItem({ id: "flag", Component: Item });
+      `),
+    );
+    expect(plugin.composerItems.map((item) => item.id)).toEqual(["flag"]);
+  });
+
+  it("rejects duplicate and non-component composer items", () => {
+    expect(() =>
+      evaluatePluginClientBundle(
+        "review",
+        bundle(`
+          function Item() { return null; }
+          plugin.addComposerItem({ id: "flag", Component: Item });
+          plugin.addComposerItem({ id: "flag", Component: Item });
+        `),
+      ),
+    ).toThrow("Duplicate composer item: flag");
+    expect(() =>
+      evaluatePluginClientBundle(
+        "review",
+        bundle(`plugin.addComposerItem({ id: "flag", Component: "nope" })`),
+      ),
+    ).toThrow("Composer item flag is not a component");
+  });
+
   it("runs the client entry with the full runtime context", () => {
     const plugin = evaluatePluginClientBundle(
       "review",

packages/app/src/plugins/evaluate.ts

@@ -131,6 +131,7 @@ export function runPluginClientBundle(
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],
@@ -146,6 +147,7 @@ export function runPluginClientBundle(
     footer: new Set(),
   };
   const filePanelIds = new Set<string>();
+  const composerItemIds = new Set<string>();
   const workspacePanelIds = new Set<string>();
   const commandCenterItemIds = new Set<string>();
   const clientSlashCommandNames = new Set<string>();
@@ -269,6 +271,20 @@ export function runPluginClientBundle(
         () => surfaceIds.delete(normalizedId),
       );
     },
+    addComposerItem(contribution) {
+      const normalizedId = requireId(contribution.id, "composer item id");
+      if (composerItemIds.has(normalizedId))
+        throw new Error(`Duplicate composer item: ${normalizedId}`);
+      if (!isComponentType(contribution.Component)) {
+        throw new Error(`Composer item ${normalizedId} is not a component`);
+      }
+      composerItemIds.add(normalizedId);
+      return register(
+        collector.composerItems,
+        { id: normalizedId, Component: contribution.Component },
+        () => composerItemIds.delete(normalizedId),
+      );
+    },
     addSidebarHeaderItem(contribution: PluginSidebarItemContribution) {
       return addSidebarItem("header", contribution);
     },
@@ -585,6 +601,7 @@ export function runPluginClientBundle(
     sidebarItems: collector.sidebarItems,
     legacySidebarItems: collector.legacySidebarItems,
     filePanels: collector.filePanels,
+    composerItems: collector.composerItems,
     workspacePanels: collector.workspacePanels as EvaluatedPlugin["workspacePanels"],
     commandCenterItems: collector.commandCenterItems,
     clientSlashCommands: collector.clientSlashCommands,

packages/app/src/plugins/freeze.ts

@@ -0,0 +1,12 @@
+/** A deep copy no plugin can change. Plugins read data through it, never the host's own objects. */
+export function cloneAndFreeze<T>(value: T): T {
+  if (Array.isArray(value)) {
+    return Object.freeze(value.map((entry) => cloneAndFreeze(entry))) as T;
+  }
+  if (value !== null && typeof value === "object") {
+    return Object.freeze(
+      Object.fromEntries(Object.entries(value).map(([key, entry]) => [key, cloneAndFreeze(entry)])),
+    ) as T;
+  }
+  return value;
+}

packages/app/src/plugins/installation-provider.test.tsx

@@ -36,6 +36,7 @@ function installation(invoked: string[]): InstalledPlugin {
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/react-native/composer-controls.tsx

@@ -0,0 +1,87 @@
+import type { ActionProps, SelectProps, ToggleProps } from "@getpaseo/plugin/client/ui";
+import { useMemo, useState } from "react";
+import {
+  ComposerControl,
+  useComposerControlSurface,
+  type ComposerControlItem,
+} from "@/composer/agent-controls/composer-control";
+import { useComposerLocked } from "@/composer/session";
+import { parsePluginIcon, pluginIconComponent } from "../icons";
+
+/** Icons resolve at render, so an invalid one throws to the item's boundary. */
+function usePluginControlIcon(icon: ToggleProps["icon"]) {
+  return useMemo(() => pluginIconComponent(parsePluginIcon("Composer control", icon)), [icon]);
+}
+
+/** Draws one plugin control where its composer item sits: inline, or as a row in the sheet. */
+function PluginComposerControl({
+  item,
+  disabled,
+}: {
+  item: ComposerControlItem;
+  disabled: boolean | undefined;
+}) {
+  const surface = useComposerControlSurface();
+  const locked = useComposerLocked();
+  const [open, setOpen] = useState(false);
+  return (
+    <ComposerControl
+      item={item}
+      surface={surface}
+      disabled={disabled || locked}
+      open={open}
+      onOpenChange={setOpen}
+    />
+  );
+}
+
+export function Toggle({ title, icon, disabled, value, onValueChange }: ToggleProps) {
+  const Icon = usePluginControlIcon(icon);
+  const item = useMemo<ComposerControlItem>(
+    () => ({
+      id: "plugin-toggle",
+      type: "toggle",
+      title,
+      icon: Icon,
+      highlight: value ? "blue" : undefined,
+      value,
+      onChange: (next) => onValueChange({ value: next }),
+    }),
+    [Icon, onValueChange, title, value],
+  );
+  return <PluginComposerControl item={item} disabled={disabled} />;
+}
+
+export function Select<Value extends string>({
+  title,
+  icon,
+  disabled,
+  value,
+  options,
+  onValueChange,
+}: SelectProps<Value>) {
+  const Icon = usePluginControlIcon(icon);
+  const item = useMemo<ComposerControlItem>(
+    () => ({
+      id: "plugin-select",
+      type: "select",
+      title,
+      icon: Icon,
+      value,
+      choices: options,
+      onChange: (next) => onValueChange({ value: next as Value }),
+      showCaret: true,
+    }),
+    [Icon, onValueChange, options, title, value],
+  );
+  return <PluginComposerControl item={item} disabled={disabled} />;
+}
+
+export function Action({ title, icon, disabled, onPress }: ActionProps) {
+  const Icon = usePluginControlIcon(icon);
+  const item = useMemo<ComposerControlItem>(
+    () => ({ id: "plugin-action", type: "action", title, icon: Icon, onPress: () => onPress({}) }),
+    [Icon, onPress, title],
+  );
+  return <PluginComposerControl item={item} disabled={disabled} />;
+}

packages/app/src/plugins/react-native/ui.ts

@@ -20,6 +20,7 @@ export { FilePanelLoading as Loading } from "@/file-panels/loading";
 export { SettingsGroup } from "@/components/settings";
 
 export { Icon } from "../icons";
+export { Action, Select, Toggle } from "./composer-controls";
 export { Modal } from "./modal";
 export { ScrollView, FlatList } from "./scroll-view";
 export { TextInput } from "./text-input";

packages/app/src/plugins/registry.ts

@@ -106,6 +106,7 @@ export class PluginRegistry {
           sidebarItems: { header: [], footer: [] },
           legacySidebarItems: [],
           filePanels: [],
+          composerItems: [],
           workspacePanels: [],
           commandCenterItems: [],
           clientSlashCommands: [],

packages/app/src/plugins/sidebar-groups.test.ts

@@ -34,6 +34,7 @@ function installed(
     },
     legacySidebarItems,
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/surface-contribution.test.ts

@@ -36,6 +36,7 @@ function installation(
       icon: "Blocks",
     })),
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/theme.test.ts

@@ -61,6 +61,7 @@ function installed(serverId: string, themes: PluginThemeContribution[]): Install
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/timeline/model.test.ts

@@ -24,6 +24,7 @@ function plugin(input: {
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [],
     commandCenterItems: [],
     clientSlashCommands: [],

packages/app/src/plugins/timeline/projection.ts

@@ -1,5 +1,6 @@
 import type { AgentTimelineItem, ToolCallTimelineItem } from "@getpaseo/protocol/agent-types";
 import type { AgentToolCallData, PluginTimelineStreamItem, StreamItem } from "@/types/stream";
+import { cloneAndFreeze } from "../freeze";
 import type { TimelineItemTransform } from "./model";
 
 type AssistantPhase = "streaming" | "complete";
@@ -9,18 +10,6 @@ const projectionCache = new WeakMap<
   WeakMap<StreamItem, Partial<Record<AssistantPhase, StreamItem[]>>>
 >();
 
-function cloneAndFreeze<T>(value: T): T {
-  if (Array.isArray(value)) {
-    return Object.freeze(value.map((entry) => cloneAndFreeze(entry))) as T;
-  }
-  if (value !== null && typeof value === "object") {
-    return Object.freeze(
-      Object.fromEntries(Object.entries(value).map(([key, entry]) => [key, cloneAndFreeze(entry)])),
-    ) as T;
-  }
-  return value;
-}
-
 function sourceToolCallTimelineItem(data: AgentToolCallData): ToolCallTimelineItem {
   const { callId, name, status, error, detail, metadata } = data;
   const base = {

packages/app/src/plugins/types.ts

@@ -11,6 +11,7 @@ import type {
   PluginFilePanelContribution as SDKPluginFilePanelContribution,
   PluginCommandCenterItemContribution as SDKPluginCommandCenterItemContribution,
   PluginClientSlashCommandContribution as SDKPluginClientSlashCommandContribution,
+  PluginComposerItemContribution,
   PluginComposerPillContribution as SDKPluginComposerPillContribution,
   PluginSidebarContribution as SDKPluginSidebarContribution,
   PluginSidebarItemContribution as SDKPluginSidebarItemContribution,
@@ -53,6 +54,7 @@ export interface EvaluatedPlugin {
   /** `addSidebarItem` registrations, so `/plugin/<id>/sidebar/<item>` routes keep resolving. */
   legacySidebarItems: PluginSidebarContribution[];
   filePanels: PluginFilePanelContribution[];
+  composerItems: PluginComposerItemContribution[];
   workspacePanels: EvaluatedPluginWorkspacePanelContribution[];
   commandCenterItems: PluginCommandCenterItemContribution[];
   clientSlashCommands: PluginClientSlashCommandContribution[];
@@ -82,6 +84,7 @@ export type {
   PluginAttachmentSourceContribution,
   PluginCommandCenterItemContribution,
   PluginClientSlashCommandContribution,
+  PluginComposerItemContribution,
   PluginComposerPillContribution,
   PluginSidebarContribution,
   PluginSidebarItemContribution,

packages/app/src/plugins/workspace-panels/resolution.test.ts

@@ -21,6 +21,7 @@ function installed(): InstalledPlugin {
     sidebarItems: { header: [], footer: [] },
     legacySidebarItems: [],
     filePanels: [],
+    composerItems: [],
     workspacePanels: [
       {
         id: "details",

packages/app/src/provider-selection/agent-form-store.ts

@@ -0,0 +1,93 @@
+import type { AgentProviderDefinition } from "@getpaseo/protocol/provider-manifest";
+import type { AgentModelDefinition, AgentProvider } from "@getpaseo/protocol/agent-types";
+import type { FormPreferences } from "@/hooks/use-form-preferences";
+import {
+  INITIAL_AGENT_FORM_RESOLUTION,
+  INITIAL_USER_MODIFIED,
+  isUnlistedModel,
+  resolveAgentForm,
+  type AgentFormAction,
+  type AgentFormReducerState,
+} from "@/provider-selection/resolve-agent-form";
+
+/** What the host offers right now. The store reads it when a command runs, never earlier. */
+export interface AgentFormCatalog {
+  /** The providers the host can run. */
+  selectableProviders: ReadonlyMap<AgentProvider, AgentProviderDefinition>;
+  /** Each provider's selectable models; empty when the host has listed none. */
+  models: ReadonlyMap<string, AgentModelDefinition[]>;
+  providerPreferences: (
+    provider: AgentProvider,
+  ) => NonNullable<FormPreferences["providerPreferences"]>[AgentProvider] | undefined;
+}
+
+/**
+ * The draft form as a plain model: `resolveAgentForm` applied synchronously. A command reads
+ * `getState()` and the catalog when it runs, so the one after `await setProvider(...)` sees the
+ * new provider instead of the render that created it.
+ */
+export interface AgentFormStore {
+  getState: () => AgentFormReducerState;
+  dispatch: (action: AgentFormAction) => void;
+  subscribe: (listener: () => void) => () => void;
+  /** `false` when the provider is unknown or not ready; the form is left as it was. */
+  setProviderAndModel: (provider: AgentProvider, modelId: string) => boolean;
+  /**
+   * `false` when the provider's catalog is loaded and does not list the model. A catalog that has
+   * not arrived keeps the id as given.
+   */
+  setModel: (modelId: string) => boolean;
+}
+
+export function openAgentForm(catalog: () => AgentFormCatalog): AgentFormStore {
+  let state: AgentFormReducerState = {
+    form: { provider: null, modeId: "", model: "", thinkingOptionId: "" },
+    userModified: INITIAL_USER_MODIFIED,
+    resolution: INITIAL_AGENT_FORM_RESOLUTION,
+  };
+  const listeners = new Set<() => void>();
+  function dispatch(action: AgentFormAction): void {
+    const next = resolveAgentForm(state, action);
+    if (next === state) return;
+    state = next;
+    for (const listener of listeners) listener();
+  }
+  return {
+    getState: () => state,
+    dispatch,
+    setProviderAndModel: (provider, modelId) => {
+      const host = catalog();
+      const providerDef = host.selectableProviders.get(provider);
+      if (!providerDef) return false;
+      dispatch({
+        type: "SET_PROVIDER_AND_MODEL_FROM_USER",
+        provider,
+        modelId,
+        providerDef,
+        providerModels: host.models.get(provider) ?? null,
+        providerPrefs: host.providerPreferences(provider),
+      });
+      return true;
+    },
+    setModel: (modelId) => {
+      const { provider } = state.form;
+      const host = catalog();
+      const listed = provider ? host.models.get(provider) : undefined;
+      const models = listed?.length ? listed : null;
+      if (isUnlistedModel(models, modelId)) return false;
+      dispatch({
+        type: "SET_MODEL_FROM_USER",
+        modelId,
+        availableModels: models,
+        providerPrefs: provider ? host.providerPreferences(provider) : undefined,
+      });
+      return true;
+    },
+    subscribe: (listener) => {
+      listeners.add(listener);
+      return () => {
+        listeners.delete(listener);
+      };
+    },
+  };
+}

packages/app/src/provider-selection/resolve-agent-form.test.ts

@@ -3,6 +3,7 @@ import {
   resolveAgentForm,
   resolveFormState,
   resolveEffectiveModel,
+  isUnlistedModel,
   resolveThinkingOptionId,
   mergeSelectedComposerPreferences,
   buildProviderDefinitionMap,
@@ -131,6 +132,19 @@ describe("resolveDefaultModel", () => {
   });
 });
 
+describe("isUnlistedModel", () => {
+  it("rejects an id the provider's catalog lacks, and accepts a listed id or alias", () => {
+    expect(isUnlistedModel(ALIASED_CODEX_MODELS, "not-in-the-catalog")).toBe(true);
+    expect(isUnlistedModel(ALIASED_CODEX_MODELS, "gpt-5.3-codex")).toBe(false);
+    expect(isUnlistedModel(ALIASED_CODEX_MODELS, "gpt-5.3-codex-legacy")).toBe(false);
+  });
+
+  it("accepts any id while the provider has listed no models", () => {
+    expect(isUnlistedModel(null, "anything")).toBe(false);
+    expect(isUnlistedModel([], "anything")).toBe(false);
+  });
+});
+
 describe("model aliases", () => {
   it("canonicalizes a retired preferred model and restores thinking from its alias key", () => {
     const resolved = resolveFormState(

packages/app/src/provider-selection/resolve-agent-form.ts

@@ -153,6 +153,19 @@ export function resolveEffectiveModel(
   return findModelByReference(availableModels, modelId) ?? null;
 }
 
+/**
+ * True when the provider has listed its models and this id is not among them. A provider that
+ * lists none accepts any id.
+ */
+export function isUnlistedModel(
+  availableModels: AgentModelDefinition[] | null,
+  modelId: string,
+): boolean {
+  if (!availableModels || availableModels.length === 0) return false;
+  if (!normalizeSelectedModelId(modelId)) return false;
+  return !resolveEffectiveModel(availableModels, modelId);
+}
+
 function resolvePreferredThinkingOptionId(input: {
   availableModels: AgentModelDefinition[] | null;
   providerPrefs: ProviderPrefs | undefined;

packages/app/src/screens/new-workspace-screen.tsx

@@ -456,6 +456,7 @@ async function createWorkspaceChatAgent(input: CreateChatAgentInput): Promise<Su
       thinkingOptionId: composerState.effectiveThinkingOptionId || undefined,
       providerOptions: composerState.providerOptions,
     },
+    ...(Object.keys(composerState.metadata).length > 0 ? { metadata: composerState.metadata } : {}),
     initialPrompt: text,
     clientMessageId: `${input.draftId}:initial-message`,
     images: images?.length ? images : undefined,
@@ -535,6 +536,7 @@ function buildComposerConfig(input: {
     initialServerId: serverId || null,
     initialValues: buildComposerInitialValues({ initialSetup }),
     initialProviderOptions: initialSetup?.providerOptions,
+    context: "new-workspace" as const,
     isVisible: true,
     lockedWorkingDir: workingDir,
   };

packages/app/src/stores/draft-store/index.ts

@@ -36,6 +36,8 @@ import {
 } from "./migration";
 import { createDraftPersistStorage } from "./persistence";
 import { createValidatedPersistStorage } from "@/storage/validated-persist-storage";
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
+import { applyMetadataPatch } from "@/composer/draft/metadata";
 
 export type { DraftInput, DraftLifecycleState } from "./state";
 
@@ -49,6 +51,9 @@ interface DraftStoreActions {
     draftKey: string;
     lifecycle?: Exclude<DraftLifecycleState, "active">;
   }) => void;
+  /** Plugin metadata the draft will create its agent with; see `composer/draft/metadata`. */
+  patchDraftMetadata: (input: { draftKey: string; patch: Record<string, JsonValue> }) => void;
+  clearDraftMetadata: (input: { draftKey: string }) => void;
   attachWorkspaceFile: (input: {
     draftKey: string;
     attachment: WorkspaceFileComposerAttachment;
@@ -60,6 +65,11 @@ interface DraftStoreActions {
 
 interface DraftStoreRuntimeState {
   attachmentFocusRequestByDraftKey: Record<string, number>;
+  /**
+   * Kept beside the prompt so a composer that remounts finds it. Not persisted, and not cleared
+   * with an emptied prompt: a plugin's choice outlives the text until the draft is sent.
+   */
+  metadataByDraftKey: Record<string, Record<string, JsonValue>>;
 }
 
 type DraftStore = DraftStoreState & DraftStoreRuntimeState & DraftStoreActions;
@@ -256,6 +266,7 @@ export const useDraftStore = create<DraftStore>()(
       drafts: {},
       createModalDraft: null,
       attachmentFocusRequestByDraftKey: {},
+      metadataByDraftKey: {},
 
       getDraftInput: (draftKey) => {
         const record = get().drafts[draftKey];
@@ -374,6 +385,25 @@ export const useDraftStore = create<DraftStore>()(
         scheduleAttachmentGc();
       },
 
+      patchDraftMetadata: ({ draftKey, patch }) => {
+        set((state) => {
+          const next = applyMetadataPatch(state.metadataByDraftKey[draftKey] ?? {}, patch);
+          const { [draftKey]: _previous, ...others } = state.metadataByDraftKey;
+          return {
+            metadataByDraftKey:
+              Object.keys(next).length > 0 ? { ...others, [draftKey]: next } : others,
+          };
+        });
+      },
+
+      clearDraftMetadata: ({ draftKey }) => {
+        set((state) => {
+          if (!(draftKey in state.metadataByDraftKey)) return state;
+          const { [draftKey]: _removed, ...others } = state.metadataByDraftKey;
+          return { metadataByDraftKey: others };
+        });
+      },
+
       attachWorkspaceFile: async ({ draftKey, attachment }) => {
         await get().hydrateDraftInput({ draftKey });
         set((state) => {

packages/app/src/stores/draft-store/metadata.test.ts

@@ -0,0 +1,35 @@
+import { beforeEach, describe, expect, it } from "vitest";
+import { useDraftStore } from "./index";
+
+const draftKey = "draft:metadata";
+
+describe("a draft's plugin metadata", () => {
+  beforeEach(() => {
+    useDraftStore.setState({ drafts: {}, metadataByDraftKey: {} });
+  });
+
+  it("is there when the draft's composer mounts again", () => {
+    const store = useDraftStore.getState();
+    store.editDraftText({ draftKey, text: "review this" });
+    store.patchDraftMetadata({ draftKey, patch: { "plugin.review": true, "plugin.tag": "a" } });
+    store.patchDraftMetadata({ draftKey, patch: { "plugin.tag": null } });
+
+    // A remount reads the store again; nothing from the unmounted composer is kept.
+    const remounted = useDraftStore.getState();
+    expect(remounted.getDraftInput(draftKey)?.text).toBe("review this");
+    expect(remounted.metadataByDraftKey[draftKey]).toEqual({ "plugin.review": true });
+  });
+
+  it("is dropped with the prompt once the draft is sent, and not before", () => {
+    const store = useDraftStore.getState();
+    store.patchDraftMetadata({ draftKey, patch: { "plugin.review": true } });
+
+    store.clearDraftInput({ draftKey, lifecycle: "abandoned" });
+    expect(useDraftStore.getState().metadataByDraftKey[draftKey]).toEqual({
+      "plugin.review": true,
+    });
+
+    store.clearDraftMetadata({ draftKey });
+    expect(useDraftStore.getState().metadataByDraftKey[draftKey]).toBeUndefined();
+  });
+});

packages/app/src/stores/session-store.ts

@@ -27,6 +27,7 @@ import type { AgentLifecycleStatus } from "@getpaseo/protocol/agent-lifecycle";
 import type {
   AgentPermissionRequest,
   AgentOptionControl,
+  JsonValue,
   ProviderOptions,
   AgentProvider,
   AgentMode,
@@ -101,6 +102,7 @@ export interface Agent {
   archivedAt?: Date | null;
   parentAgentId: string | null;
   labels: Record<string, string>;
+  metadata?: Record<string, JsonValue>;
   projectPlacement?: ProjectPlacementPayload | null;
 }
 

packages/app/src/utils/agent-snapshots.ts

@@ -82,6 +82,7 @@ export function projectAgentSnapshot(agent: Agent): AgentSnapshotPayload {
     ...(agent.lastError ? { lastError: agent.lastError } : {}),
     title: agent.title,
     labels: agent.labels,
+    ...(agent.metadata ? { metadata: agent.metadata } : {}),
     requiresAttention: agent.requiresAttention ?? false,
     attentionReason: agent.attentionReason ?? null,
     attentionTimestamp: agent.attentionTimestamp?.toISOString() ?? null,
@@ -137,5 +138,6 @@ export function normalizeAgentSnapshot(snapshot: AgentSnapshotPayload, serverId:
     archivedAt,
     parentAgentId,
     labels: snapshot.labels,
+    metadata: snapshot.metadata,
   };
 }

packages/app/test-stubs/lucide-react-native.ts

@@ -116,3 +116,8 @@ export const Maximize2 = StubIcon;
 export const Workflow = StubIcon;
 export const ZoomIn = StubIcon;
 export const ZoomOut = StubIcon;
+export const ListTodo = StubIcon;
+export const Shield = StubIcon;
+export const ShieldEllipsis = StubIcon;
+export const ShieldPlus = StubIcon;
+export const Zap = StubIcon;

packages/app/test-stubs/react-native-unistyles.ts

@@ -30,8 +30,10 @@ const testTheme = {
     borderAccent: "#a1a1aa",
     palette: {
       amber: { 500: "#f59e0b" },
-      blue: { 300: "#93c5fd" },
-      green: { 500: "#22c55e" },
+      blue: { 300: "#93c5fd", 400: "#60a5fa" },
+      green: { 400: "#4ade80", 500: "#22c55e" },
+      yellow: { 400: "#facc15" },
+      zinc: { 600: "#52525b" },
       red: { 300: "#fca5a5" },
       white: "#ffffff",
     },

packages/app/vitest.config.ts

@@ -236,6 +236,14 @@ export default defineConfig({
         find: /^react-native\/Libraries\/Renderer\/shims\/ReactFabric$/,
         replacement: path.resolve(__dirname, "test-stubs/react-native-fabric-shim.ts"),
       },
+      // The CJS entry requires the real react-native, whose Flow sources do not parse.
+      {
+        find: /^@floating-ui\/react-native$/,
+        replacement: path.resolve(
+          rootNodeModules,
+          "@floating-ui/react-native/dist/floating-ui.react-native.esm.js",
+        ),
+      },
       // Point to the ESM build so Vite can transform its imports and apply the
       // react alias below (the CJS build uses require('react') which bypasses
       // Vite alias resolution).

packages/plugin/src/boundaries.test.ts

@@ -213,6 +213,43 @@ describe("plugin panel SDK boundary", () => {
   });
 });
 
+describe("plugin composer SDK boundary", () => {
+  it("lets a composer item read and change the composer through typed commands and controls", () => {
+    expect(
+      typeErrors(`
+      import { useComposer, type PluginClientContext } from "@getpaseo/plugin/client";
+      import { Action, Select, Toggle } from "@getpaseo/plugin/client/ui";
+      function Item() {
+        const composer = useComposer();
+        const context: "agent" | "draft" | "new-workspace" = composer.context;
+        const provider: string | null = composer.agent.provider;
+        const flag: boolean = composer.agent.metadata.flag === true;
+        // @ts-expect-error reads are not writable
+        composer.agent.model = "other";
+        composer.setProvider("codex").then(() => composer.setModel("gpt"));
+        composer.setOptions({ effort: null });
+        composer.setMetadata({ flag: true, stale: null });
+        composer.insertText("text");
+        composer.addAttachment({ sourceId: "issues", item: { id: "1", identifier: "1", title: "t", url: "https://e.com", text: "t", resourceType: "issue" } });
+        // @ts-expect-error commands take JSON values
+        composer.setMetadata({ fn: () => {} });
+        return (
+          <>
+            <Toggle title="Flag" icon="Flag" value={flag} onValueChange={({ value }: { value: boolean }) => composer.setMetadata({ flag: value })} />
+            <Select title="Size" icon="Gauge" value="a" options={[{ value: "a", label: "A" }, { value: "b", label: "B" }]} onValueChange={({ value }: { value: "a" | "b" }) => {}} />
+            <Action title="Insert" icon="Plus" onPress={() => composer.setPrompt("")} />
+          </>
+        );
+      }
+      export default function contribute(client: PluginClientContext) {
+        client.addComposerItem({ id: "item", Component: Item });
+        return () => {};
+      }
+    `),
+    ).toEqual([]);
+  });
+});
+
 describe("plugin agent tools SDK boundary", () => {
   it("lets a session hook attach typed tools without exposing their transport", () => {
     expect(

packages/plugin/src/client/composer.tsx

@@ -0,0 +1,78 @@
+import { createContext, useContext, type ComponentType, type ReactNode } from "react";
+import type { JsonValue } from "@getpaseo/protocol/agent-types";
+import type { PluginAttachmentItem } from "../attachments.js";
+import type { PluginHostProps } from "./contracts.js";
+
+/** One item the user attached from a source this plugin registered with `addAttachmentSource`. */
+export interface PluginComposerAttachment {
+  readonly sourceId: string;
+  readonly item: PluginAttachmentItem;
+}
+
+/**
+ * The composer the item sits in: the prompt, the attachments and the agent being configured.
+ * The commands behave the same in every composer. `context` says where the composer is; it does
+ * not change what a command does, except that a running agent keeps its provider.
+ */
+export interface PluginComposer {
+  /** `"agent"`: a running agent. `"draft"`: a new agent in a workspace. `"new-workspace"`: the New workspace screen. */
+  readonly context: "agent" | "draft" | "new-workspace";
+  readonly prompt: string;
+  /** This plugin's attachments only. */
+  readonly attachments: readonly PluginComposerAttachment[];
+  readonly agent: {
+    readonly provider: string | null;
+    readonly model: string | null;
+    readonly mode: string | null;
+    readonly thinking: string | null;
+    /** The options the agent runs with, including provider defaults. */
+    readonly options: Readonly<Record<string, JsonValue>>;
+    readonly metadata: Readonly<Record<string, JsonValue>>;
+  };
+  setPrompt(text: string): void;
+  /** Inserts at the cursor, replacing the selection. */
+  insertText(text: string): void;
+  addAttachment(input: { sourceId: string; item: PluginAttachmentItem }): void;
+  removeAttachment(input: { sourceId: string; itemId: string }): void;
+  /** Resets the model like the built-in control. Rejects on a running agent, which keeps its provider. */
+  setProvider(provider: string): Promise<void>;
+  setModel(modelId: string): Promise<void>;
+  setMode(modeId: string): Promise<void>;
+  setThinking(thinkingOptionId: string): Promise<void>;
+  /** Top-level keys replace; `null` removes the agent's own value. */
+  setOptions(patch: Record<string, JsonValue>): Promise<void>;
+  /** Top-level keys replace; `null` removes the key. */
+  setMetadata(patch: Record<string, JsonValue>): Promise<void>;
+}
+
+export interface PluginComposerItemProps extends PluginHostProps {}
+
+export interface PluginComposerItemContribution {
+  id: string;
+  Component: ComponentType<PluginComposerItemProps>;
+}
+
+const PluginComposerContext = createContext<PluginComposer | null>(null);
+
+export function PluginComposerProvider({
+  composer,
+  children,
+}: {
+  composer: PluginComposer;
+  children: ReactNode;
+}) {
+  return (
+    <PluginComposerContext.Provider value={composer}>{children}</PluginComposerContext.Provider>
+  );
+}
+
+export function usePluginComposerValue(): PluginComposer | null {
+  return useContext(PluginComposerContext);
+}
+
+/** The composer this item sits in. Call it from a component registered with `addComposerItem`. */
+export function useComposer(): PluginComposer {
+  const composer = usePluginComposerValue();
+  if (!composer) throw new Error("useComposer must run inside a composer item");
+  return composer;
+}

packages/plugin/src/client/contracts.ts

@@ -4,6 +4,7 @@ import type { PaseoApi } from "@getpaseo/client";
 import type { AgentTimelineItem, JsonValue } from "@getpaseo/protocol/agent-types";
 import type { ZodType, input as ZodInput, output as ZodOutput } from "zod";
 import type { PluginFile } from "./file.js";
+import type { PluginComposerItemContribution } from "./composer.js";
 import type { PluginRpcContract } from "../rpc.js";
 import type {
   PluginButtonRegistration,
@@ -194,6 +195,7 @@ export interface PluginClientContext extends PluginCommandCapabilities, PluginCl
     contribution: PluginComposerPillContribution<PluginText>,
   ): PluginButtonRegistration<PluginText>;
   addAttachmentSource(contribution: PluginAttachmentSourceContribution<PluginText>): PluginCleanup;
+  addComposerItem(contribution: PluginComposerItemContribution): PluginCleanup;
   addTheme(contribution: PluginThemeContribution<PluginText>): PluginCleanup;
   addFilePanel(contribution: PluginFilePanelContribution<PluginText>): PluginCleanup;
   addTimelineTransformer<ItemType extends AgentTimelineItem["type"]>(

packages/plugin/src/client/host.ts

@@ -1,6 +1,7 @@
 import type { PluginText } from "../text.js";
 import { PluginAttachmentSearchPayloadSchema } from "../attachments.js";
 export { PluginClientStateProvider, type PluginClientStateSource } from "./client-state.js";
+export { PluginComposerProvider } from "./composer.js";
 export {
   usePluginRuntimeContextBridge,
   type PluginRuntimeContextBridge,

packages/plugin/src/client/index.ts

@@ -71,6 +71,13 @@ export {
 } from "./file.js";
 export { usePaseo } from "./paseo-context.js";
 export { useAgent, useWorkspace } from "./client-state.js";
+export { useComposer } from "./composer.js";
+export type {
+  PluginComposer,
+  PluginComposerAttachment,
+  PluginComposerItemContribution,
+  PluginComposerItemProps,
+} from "./composer.js";
 export { useRpc } from "./rpc-context.js";
 import type { SettingsDefinition } from "../settings.js";
 import type { SettingsState } from "./contracts.js";

packages/plugin/src/client/runtime-context-bridge.tsx

@@ -1,5 +1,6 @@
 import { PluginTranslationProvider, usePluginTranslationRuntime } from "./translations.js";
 import { useCallback, type ReactNode } from "react";
+import { PluginComposerProvider, usePluginComposerValue } from "./composer.js";
 import { PluginClientStateProvider, usePluginClientStateSource } from "./client-state.js";
 import { PaseoApiProvider, usePaseoContextValue } from "./paseo-context.js";
 import { PluginRpcProvider, usePluginRpcContextValue } from "./rpc-context.js";
@@ -12,6 +13,7 @@ export function usePluginRuntimeContextBridge(): PluginRuntimeContextBridge {
   const paseo = usePaseoContextValue();
   const rpc = usePluginRpcContextValue();
   const state = usePluginClientStateSource();
+  const composer = usePluginComposerValue();
 
   if (!paseo || !rpc) {
     throw new Error("Plugin UI must run inside a contributed plugin surface");
@@ -19,11 +21,16 @@ export function usePluginRuntimeContextBridge(): PluginRuntimeContextBridge {
 
   return useCallback(
     (children: ReactNode) => {
-      const content = state ? (
+      const withState = state ? (
         <PluginClientStateProvider source={state}>{children}</PluginClientStateProvider>
       ) : (
         children
       );
+      const content = composer ? (
+        <PluginComposerProvider composer={composer}>{withState}</PluginComposerProvider>
+      ) : (
+        withState
+      );
       return (
         <PaseoApiProvider paseo={paseo}>
           <PluginRpcProvider invoke={rpc.invoke}>
@@ -32,6 +39,6 @@ export function usePluginRuntimeContextBridge(): PluginRuntimeContextBridge {
         </PaseoApiProvider>
       );
     },
-    [paseo, rpc, state, translations],
+    [composer, paseo, rpc, state, translations],
   );
 }

packages/plugin/src/client/ui.ts

@@ -185,3 +185,35 @@ export interface MarkdownProps {
 
 /** Renders Markdown using Paseo’s theme, selection, and link behavior. */
 export declare const Markdown: ComponentType<MarkdownProps>;
+
+export interface ComposerControlProps {
+  /** The control's label and tooltip. */
+  title: string;
+  /** A Lucide icon name, inline SVG, or a component. */
+  icon: PluginIcon;
+  disabled?: boolean;
+}
+/**
+ * What a control's callback receives. A returned promise marks the control pending until it
+ * settles, and Paseo reports a rejection to the user.
+ */
+export interface ToggleProps extends ComposerControlProps {
+  value: boolean;
+  onValueChange(event: { value: boolean }): void | Promise<void>;
+}
+export interface SelectProps<Value extends string = string> extends ComposerControlProps {
+  value: Value;
+  options: readonly { value: Value; label: string; description?: string }[];
+  onValueChange(event: { value: Value }): void | Promise<void>;
+}
+export interface ActionPressEvent {}
+export interface ActionProps extends ComposerControlProps {
+  onPress(event: ActionPressEvent): void | Promise<void>;
+}
+/**
+ * Composer controls. Render them from a composer item's `Component`. Paseo draws them inline when
+ * the composer has room and as rows in its overflow sheet when it does not.
+ */
+export declare const Toggle: ComponentType<ToggleProps>;
+export declare function Select<Value extends string>(props: SelectProps<Value>): ReactNode;
+export declare const Action: ComponentType<ActionProps>;

packages/plugin/src/contracts.ts

@@ -52,6 +52,8 @@ export interface PluginAgentSnapshot {
   readonly attentionReason: "finished" | "error" | "permission" | null;
   readonly parentAgentId: string | null;
   readonly labels: Readonly<Record<string, string>>;
+  /** Structured data plugins store on the agent. */
+  readonly metadata: Readonly<Record<string, JsonValue>>;
 }
 
 export interface PluginThemeColors {

plugin-examples/composer-controls/README.md

@@ -0,0 +1,18 @@
+# Composer controls
+
+Install this directory as a plugin and open the agent, draft, or New workspace composer. Four
+controls appear beside the model and thinking controls.
+
+| Control              | Component | What it does                                                                             |
+| -------------------- | --------- | ---------------------------------------------------------------------------------------- |
+| **Context length**   | `Select`  | Saves `composer-controls.contextLength` in the agent's metadata.                         |
+| **Needs review**     | `Toggle`  | Sets or clears `composer-controls.needsReview` in the agent's metadata.                  |
+| **Plan first**       | `Toggle`  | Sets the provider option `plan_mode` with `composer.setOptions`; enabled for Codex only. |
+| **Insert checklist** | `Action`  | Inserts a task list at the cursor through `composer.insertText`.                         |
+
+Each component calls `useComposer()` and uses the same commands in every composer. Paseo draws the
+controls inline when the composer has room and as rows in the composer's overflow sheet when it
+does not, including on a phone.
+
+[client/controls.tsx](client/controls.tsx) holds the four components; [index.client.tsx](index.client.tsx)
+registers them with `addComposerItem`.

plugin-examples/composer-controls/client/controls.tsx

@@ -0,0 +1,77 @@
+import { useCallback } from "react";
+import { useComposer } from "@getpaseo/plugin/client";
+import { Action, Select, Toggle } from "@getpaseo/plugin/client/ui";
+
+type ContextLength = "short" | "long";
+
+const CONTEXT_OPTIONS = [
+  { value: "short", label: "Short", description: "Answer from the files you name." },
+  { value: "long", label: "Long", description: "Read the surrounding code first." },
+] as const;
+
+const CONTEXT_KEY = "composer-controls.contextLength";
+const REVIEW_KEY = "composer-controls.needsReview";
+
+/** Reads and writes agent metadata, so the choice is saved with the agent. */
+export function ContextLength() {
+  const composer = useComposer();
+  const current: ContextLength = composer.agent.metadata[CONTEXT_KEY] === "long" ? "long" : "short";
+  const change = useCallback(
+    ({ value }: { value: ContextLength }) => composer.setMetadata({ [CONTEXT_KEY]: value }),
+    [composer],
+  );
+  return (
+    <Select
+      title="Context length"
+      icon="Gauge"
+      value={current}
+      options={CONTEXT_OPTIONS}
+      onValueChange={change}
+    />
+  );
+}
+
+export function ReviewFlag() {
+  const composer = useComposer();
+  const change = useCallback(
+    ({ value }: { value: boolean }) => composer.setMetadata({ [REVIEW_KEY]: value ? true : null }),
+    [composer],
+  );
+  return (
+    <Toggle
+      title="Needs review"
+      icon="Flag"
+      value={composer.agent.metadata[REVIEW_KEY] === true}
+      onValueChange={change}
+    />
+  );
+}
+
+/**
+ * Changes a provider option. Only Codex reports `plan_mode`, so the control is disabled for
+ * other providers. The promise it returns keeps the control pending, and a rejection reaches the
+ * user as a toast.
+ */
+export function PlanFirst() {
+  const composer = useComposer();
+  const change = useCallback(
+    ({ value }: { value: boolean }) => composer.setOptions({ plan_mode: value }),
+    [composer],
+  );
+  return (
+    <Toggle
+      title="Plan first"
+      icon="ListTodo"
+      disabled={composer.agent.provider !== "codex"}
+      value={composer.agent.options.plan_mode === true}
+      onValueChange={change}
+    />
+  );
+}
+
+/** Works the same in the agent, draft and New workspace composers. */
+export function Checklist() {
+  const composer = useComposer();
+  const insert = useCallback(() => composer.insertText("- [ ] Tests\n- [ ] Docs\n"), [composer]);
+  return <Action title="Insert checklist" icon="ListChecks" onPress={insert} />;
+}

plugin-examples/composer-controls/index.client.tsx

@@ -0,0 +1,10 @@
+import type { PluginClientContext } from "@getpaseo/plugin/client";
+import { Checklist, ContextLength, PlanFirst, ReviewFlag } from "./client/controls";
+
+export default function contribute(client: PluginClientContext) {
+  client.addComposerItem({ id: "context-length", Component: ContextLength });
+  client.addComposerItem({ id: "review-flag", Component: ReviewFlag });
+  client.addComposerItem({ id: "plan-first", Component: PlanFirst });
+  client.addComposerItem({ id: "checklist", Component: Checklist });
+  return () => {};
+}

plugin-examples/composer-controls/paseo-plugin.json

@@ -0,0 +1,4 @@
+{
+  "id": "composer-controls-example",
+  "requirements": { "paseo": ">=0.8.0" }
+}

public-docs/plugins/index.md

@@ -14,6 +14,7 @@ A plugin is a TypeScript project installed into one Paseo daemon. It can add
 [file panels](/docs/plugins/reference#file-panels),
 [Command Center items](/docs/plugins/reference#command-center-items),
 [slash commands](/docs/plugins/reference#slash-commands),
+[composer items](/docs/plugins/reference#composer-items),
 [composer pills](/docs/plugins/reference#composer-pills),
 [timeline items](/docs/plugins/reference#timeline-items),
 [themes](/docs/plugins/reference#contribute-a-theme),

public-docs/plugins/index.zh-CN.md

@@ -6,7 +6,7 @@ nav: 快速上手
 
 # 插件快速上手 {#plugin-quickstart}
 
-插件是安装到某个 Paseo daemon 中的 TypeScript 项目。它可以添加[界面和侧边栏项](/docs/plugins/reference#screens-and-sidebar-items)、[工作区面板](/docs/plugins/reference#workspace-panels)、[文件面板](/docs/plugins/reference#file-panels)、[Command Center 项](/docs/plugins/reference#command-center-items)、[斜杠命令](/docs/plugins/reference#slash-commands)、[Composer 标签](/docs/plugins/reference#composer-pills)、[时间线条目](/docs/plugins/reference#timeline-items)、[主题](/docs/plugins/reference#contribute-a-theme)、[附件来源](/docs/plugins/reference#add-a-composer-attachment-source)和 [daemon 端 RPC](/docs/plugins/reference#add-plugin-specific-backend-behavior)。它还可以[把编程 Agent 接入为 Provider](/docs/plugins/providers)。客户端贡献会在连接到该 daemon 的每个 Paseo 客户端上运行，包括移动端。
+插件是安装到某个 Paseo daemon 中的 TypeScript 项目。它可以添加[界面和侧边栏项](/docs/plugins/reference#screens-and-sidebar-items)、[工作区面板](/docs/plugins/reference#workspace-panels)、[文件面板](/docs/plugins/reference#file-panels)、[Command Center 项](/docs/plugins/reference#command-center-items)、[斜杠命令](/docs/plugins/reference#slash-commands)、[Composer 项](/docs/plugins/reference#composer-items)、[Composer 标签](/docs/plugins/reference#composer-pills)、[时间线条目](/docs/plugins/reference#timeline-items)、[主题](/docs/plugins/reference#contribute-a-theme)、[附件来源](/docs/plugins/reference#add-a-composer-attachment-source)和 [daemon 端 RPC](/docs/plugins/reference#add-plugin-specific-backend-behavior)。它还可以[把编程 Agent 接入为 Provider](/docs/plugins/providers)。客户端贡献会在连接到该 daemon 的每个 Paseo 客户端上运行，包括移动端。
 
 浏览[已发布的插件](https://paseo.sh/plugins)，然后在你的 daemon 上安装一个：
 

public-docs/plugins/migration.md

@@ -80,6 +80,7 @@ Use this table as the complete registration checklist.
 | `plugin.addClientSlashCommand(command)` in the old root entry                                 | `client.addSlashCommand(command)` in `index.client.tsx`                                                                     |
 | `plugin.addClientSide(fn)` in the old root entry                                              | Delete the wrapper and move the body of `fn` into the default client entry function                                         |
 | `client.addComposerPill(pill)` inside the old client callback                                 | `client.addComposerPill(pill)` inside `index.client.tsx` or an imported `client/` function                                  |
+| New composer item contribution                                                                | `client.addComposerItem(item)` in `index.client.tsx`; see [composer items](reference#composer-items)                        |
 | New header contribution                                                                       | `client.addHeaderButton({ id, workspaceId, button })`                                                                       |
 | `plugin.addAttachmentSource(source)` in the old root entry                                    | `client.addAttachmentSource(source)` in `index.client.tsx`                                                                  |
 | New settings screen contribution                                                              | `client.addSettingsScreen(screen)` in `index.client.tsx`; see [settings screens](reference#settings-screens)                |

public-docs/plugins/migration.zh-CN.md

@@ -73,6 +73,7 @@ my-plugin/
 | 旧根入口中的 `plugin.addClientSlashCommand(command)`                                          | `index.client.tsx` 中的 `client.addSlashCommand(command)`                                                              |
 | 旧根入口中的 `plugin.addClientSide(fn)`                                                       | 删除这层包装，把 `fn` 的函数体移入默认的客户端入口函数                                                                 |
 | 旧客户端回调中的 `client.addComposerPill(pill)`                                               | `index.client.tsx` 或被导入的 `client/` 函数中的 `client.addComposerPill(pill)`                                        |
+| 新的编辑器项贡献                                                                              | `index.client.tsx` 中的 `client.addComposerItem(item)`;见[编辑器项](reference#composer-items)                          |
 | 新的标题栏贡献                                                                                | `client.addHeaderButton({ id, workspaceId, button })`                                                                  |
 | 旧根入口中的 `plugin.addAttachmentSource(source)`                                             | `index.client.tsx` 中的 `client.addAttachmentSource(source)`                                                           |
 | 新的设置界面贡献                                                                              | `index.client.tsx` 中的 `client.addSettingsScreen(screen)`；见[设置界面](reference#settings-screens)                   |

public-docs/plugins/reference.md

@@ -1894,6 +1894,93 @@ header has no room for plugin buttons, so each one is a row of the workspace men
 icon and title; its menus and popovers open as pages of that sheet. Placement and overflow are host
 decisions.
 
+## Composer items
+
+`client.addComposerItem({ id, Component })` puts a component in the composer: the agent composer,
+the draft composer for a new agent, and the composer on the New workspace screen. `useComposer()`
+reads and changes what the composer configures, and `Toggle`, `Select` and `Action` from
+`@getpaseo/plugin/client/ui` draw the controls.
+
+```tsx
+import { useComposer, type PluginClientContext } from "@getpaseo/plugin/client";
+import { Action, Select, Toggle } from "@getpaseo/plugin/client/ui";
+
+function ReviewFlag() {
+  const composer = useComposer();
+  return (
+    <Toggle
+      title="Needs review"
+      icon="Flag"
+      value={composer.agent.metadata["review.needsReview"] === true}
+      onValueChange={({ value }) =>
+        composer.setMetadata({ "review.needsReview": value ? true : null })
+      }
+    />
+  );
+}
+
+function Checklist() {
+  const composer = useComposer();
+  return (
+    <Action
+      title="Insert checklist"
+      icon="ListChecks"
+      onPress={() => composer.insertText("- [ ] Tests\n- [ ] Docs\n")}
+    />
+  );
+}
+
+export default function contribute(client: PluginClientContext) {
+  client.addComposerItem({ id: "review-flag", Component: ReviewFlag });
+  client.addComposerItem({ id: "checklist", Component: Checklist });
+  return () => {};
+}
+```
+
+`useComposer()` returns the composer the item sits in:
+
+| Field or command                                    | Meaning                                                                                                                                                                                                                                                       |
+| --------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `context`                                           | `"agent"` for a running agent, `"draft"` for a new agent in a workspace, `"new-workspace"` for the New workspace screen.                                                                                                                                      |
+| `prompt`, `setPrompt(text)`, `insertText(text)`     | The prompt. `insertText` replaces the selection or inserts at the cursor.                                                                                                                                                                                     |
+| `attachments`, `addAttachment`, `removeAttachment`  | Items from [your own attachment sources](#add-a-composer-attachment-source). Attachments from other plugins and Paseo's own are not listed.                                                                                                                   |
+| `agent.provider`, `model`, `mode`, `thinking`       | What the agent runs with, or what the draft will create.                                                                                                                                                                                                      |
+| `agent.options`                                     | The provider options in effect, defaults included. In a draft: the options the agent will be created with, including your changes.                                                                                                                            |
+| `agent.metadata`                                    | The agent's [metadata](/docs/plugins/hooks#metadata). In New workspace, the first agent's.                                                                                                                                                                    |
+| `setProvider`, `setModel`, `setMode`, `setThinking` | Return promises. `setProvider` resets the model like the provider picker. It rejects on `context: "agent"`, which keeps its provider, and for a provider the host does not offer. `setModel` rejects for a model the provider's loaded catalog does not list. |
+| `setOptions(patch)`, `setMetadata(patch)`           | Top-level keys replace; `null` removes the key. Metadata set in a draft is sent when the agent is created and cleared once the prompt is sent.                                                                                                                |
+
+The same call does the same thing in every composer; a plugin does not choose a composer's
+implementation. `setMetadata` on a running agent needs a host that supports metadata. On an older
+host the promise rejects with "Update the host to use metadata."
+
+`Toggle` takes `value` and `onValueChange({ value })`. `Select` takes `value`, `options` (`{ value, label,
+description? }`) and `onValueChange({ value })`. `Action` takes `onPress(event)`. All three take `title`,
+`icon` (a [Lucide name, SVG or component](#icons)) and `disabled`. A callback may return a promise:
+the control stays disabled until it settles, and Paseo shows a rejection to the user as an error
+toast, the way it does for its own controls. Paseo owns where each control sits: inline in the
+toolbar when the composer has room, and a row in the composer's overflow sheet when it does not,
+which is always the case on a phone. A `Select` opens its list in place of the sheet row. A
+`Component` that renders something other than these controls draws it where its item is placed; in
+the overflow sheet that is the sheet.
+
+Each command acts on the composer's state when it runs, not on the render that created your
+callback, so `await composer.setProvider("codex")` followed by `await composer.setModel("gpt")`
+changes both. A command's promise resolves once the change has taken effect, and `composer.agent`
+shows it on the next render.
+
+While the New workspace screen creates the workspace and its agent, the composer is locked. Your
+controls render disabled, `setPrompt` and `insertText` throw, and the agent commands reject with
+"The composer is locked while the agent is being created." `composer.agent.options` and
+`composer.agent.metadata` are frozen copies; change them through `setOptions` and `setMetadata`.
+
+A composer item counts toward how much fits before Paseo knows what it renders. An item that
+renders nothing can still leave an empty overflow sheet on a narrow composer, so always render a
+control.
+
+The [composer controls example](https://github.com/getpaseo/paseo/tree/main/plugin-examples/composer-controls)
+registers a `Select`, two `Toggle`s (one writes a provider option) and an `Action`.
+
 ## Composer pills
 
 `client.addComposerPill({ id, workspaceId, agentId, button })` uses the same [button descriptor](#button-descriptor)

public-docs/plugins/reference.zh-CN.md

@@ -1600,6 +1600,71 @@ review.remove();
 贡献移入一个共享的溢出菜单。在手机和较窄的窗口中，标题栏没有空间放置插件按钮，因此每个按钮都会成为工作区
 菜单（`···`）中的一行，显示它的图标和标题；它的菜单和弹出框以该底部面板中的页面打开。位置和溢出由宿主决定。
 
+## Composer 项 {#composer-items}
+
+`client.addComposerItem({ id, Component })` 把一个组件放进 composer：Agent composer、为新 Agent 准备的草稿 composer，以及新建工作区界面上的 composer。`useComposer()` 读取并修改 composer 所配置的内容，`@getpaseo/plugin/client/ui` 中的 `Toggle`、`Select` 和 `Action` 负责绘制控件。
+
+```tsx
+import { useComposer, type PluginClientContext } from "@getpaseo/plugin/client";
+import { Action, Select, Toggle } from "@getpaseo/plugin/client/ui";
+
+function ReviewFlag() {
+  const composer = useComposer();
+  return (
+    <Toggle
+      title="Needs review"
+      icon="Flag"
+      value={composer.agent.metadata["review.needsReview"] === true}
+      onValueChange={({ value }) =>
+        composer.setMetadata({ "review.needsReview": value ? true : null })
+      }
+    />
+  );
+}
+
+function Checklist() {
+  const composer = useComposer();
+  return (
+    <Action
+      title="Insert checklist"
+      icon="ListChecks"
+      onPress={() => composer.insertText("- [ ] Tests\n- [ ] Docs\n")}
+    />
+  );
+}
+
+export default function contribute(client: PluginClientContext) {
+  client.addComposerItem({ id: "review-flag", Component: ReviewFlag });
+  client.addComposerItem({ id: "checklist", Component: Checklist });
+  return () => {};
+}
+```
+
+`useComposer()` 返回该项所在的 composer：
+
+| 字段或命令                                          | 含义                                                                                                                                                                                                                           |
+| --------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
+| `context`                                           | `"agent"` 表示运行中的 Agent，`"draft"` 表示工作区中的新 Agent，`"new-workspace"` 表示新建工作区界面。                                                                                                                         |
+| `prompt`、`setPrompt(text)`、`insertText(text)`     | 提示词。`insertText` 会替换选区，或在光标处插入。                                                                                                                                                                              |
+| `attachments`、`addAttachment`、`removeAttachment`  | 来自[你自己的附件来源](#add-a-composer-attachment-source)的项目。其他插件和 Paseo 自身的附件不会列出。                                                                                                                         |
+| `agent.provider`、`model`、`mode`、`thinking`       | Agent 当前使用的配置，或草稿将要创建的配置。                                                                                                                                                                                   |
+| `agent.options`                                     | 当前生效的 Provider 选项，包含默认值。在草稿中：创建 Agent 时将使用的选项，包含你所做的修改。                                                                                                                                  |
+| `agent.metadata`                                    | Agent 的[元数据](/docs/plugins/hooks#metadata)。在新建工作区中是第一个 Agent 的元数据。                                                                                                                                        |
+| `setProvider`、`setModel`、`setMode`、`setThinking` | 返回 Promise。`setProvider` 会像 Provider 选择器一样重置模型。在 `context: "agent"` 下（运行中的 Agent 保持其 Provider）以及主机不提供该 Provider 时会被拒绝。Provider 的模型目录已加载但未列出该模型时，`setModel` 会被拒绝。 |
+| `setOptions(patch)`、`setMetadata(patch)`           | 顶层键替换，`null` 删除该键。草稿中设置的元数据在创建 Agent 时发送，发送提示词后清空。                                                                                                                                         |
+
+同一个调用在每个 composer 中行为一致，插件不需要选择 composer 的实现。在运行中的 Agent 上调用 `setMetadata` 需要支持元数据的主机；主机过旧时，Promise 会以 “Update the host to use metadata.” 拒绝。
+
+`Toggle` 接收 `value` 和 `onValueChange({ value })`。`Select` 接收 `value`、`options`（`{ value, label, description? }`）和 `onValueChange({ value })`。`Action` 接收 `onPress(event)`。三者都接收 `title`、`icon`（[Lucide 名称、SVG 或组件](#icons)）和 `disabled`。回调可以返回 Promise：在它完成之前控件保持禁用，被拒绝时 Paseo 会像对待自身控件一样，以错误提示向用户显示。控件的位置由 Paseo 决定：composer 空间足够时显示在工具栏中，不够时（手机上始终如此）成为 composer 溢出面板中的一行。`Select` 会就地打开列表，而不是替换面板中的行。`Component` 如果渲染这些控件以外的内容，会在其所在位置绘制；在溢出面板中，该位置就是面板。
+
+每个命令都按运行时 composer 的当前状态执行，而不是按创建回调的那次渲染，所以 `await composer.setProvider("codex")` 之后再 `await composer.setModel("gpt")` 会同时生效。命令的 Promise 在更改生效后完成，`composer.agent` 在下一次渲染时反映它。
+
+新建工作区界面在创建工作区及其 Agent 期间会锁定 composer。你的控件显示为禁用，`setPrompt` 和 `insertText` 会抛出错误，Agent 命令会以 "The composer is locked while the agent is being created." 拒绝。`composer.agent.options` 和 `composer.agent.metadata` 是冻结的副本；请通过 `setOptions` 和 `setMetadata` 修改它们。
+
+在 Paseo 知道渲染结果之前，composer 项就已计入可容纳的数量。不渲染任何内容的项仍可能在窄 composer 上留下空的溢出面板，所以请始终渲染一个控件。
+
+[Composer 控件示例](https://github.com/getpaseo/paseo/tree/main/plugin-examples/composer-controls)注册了一个 `Select`、两个 `Toggle`（其中一个写入 Provider 选项）和一个 `Action`。
+
 ## Composer 胶囊 {#composer-pills}
 
 `client.addComposerPill({ id, workspaceId, agentId, button })` 使用同样的[按钮描述符](#button-descriptor)，