paseo/docs/plugins.md

Plugins

Local plugins contribute daemon RPCs, native app surfaces, workspace panels, Command Center items, client slash commands, timeline items, header buttons, composer pills, app themes, composer attachment sources, and settings screens. Paseo executes index.server.ts in a subprocess and index.client.tsx in every connected app.

Trust every plugin you add. paseo plugin add and paseo plugin install mean “I trust this codebase.” Plugins are unsandboxed: server code and preparation commands run with the daemon user's access on the daemon host, and client contributions run inside Paseo. The repository's dependencies and future updates are part of that trust decision. With --host, preparation runs on that remote daemon host.

Install a directory source

Create a typecheckable plugin project, install its development dependencies, then install it into the daemon. init only writes the project files; it does not run the package manager.

paseo plugin init /absolute/path/to/my-plugin
cd /absolute/path/to/my-plugin
npm install
npm run typecheck
paseo plugin install /absolute/path/to/my-plugin
paseo plugin install /absolute/path/to/my-plugin --id another-runtime-id
paseo plugin ls

The daemon stores directory sources under the root plugins object:

{
  "pluginsEnabled": true,
  "plugins": {
    "my-plugin": {
      "source": "directory",
      "path": "/absolute/path/to/my-plugin",
      "enabled": true
    }
  }
}

Installed plugins are disabled unless pluginsEnabled is true. Built-in plugins remain active. Changing that root field is runtime-safe: run paseo reload after editing config.json. Enabling starts every configured, enabled plugin; disabling tears them all down without restarting the daemon. Plugin source entries remain lifecycle-owned and do not reload from manual config edits.

The directory contains a manifest declaring identity and Paseo requirements, one optional entry per runtime, runtime-owned directories, and local typechecking support. At least one entry is required.

my-plugin/
  paseo-plugin.json
  package.json
  tsconfig.json
  index.client.tsx
  index.server.ts
  client/greeting.tsx
  server/greeting.ts
  shared/greeting.ts

The generated package.json installs @getpaseo/plugin and the other host modules as development dependencies for local typechecking and tests. Paseo compiles TypeScript and TSX and supplies the runtime modules, so consumers do not install these packages when adding the plugin.

{
  "id": "my-plugin",
  "requirements": { "paseo": ">=0.8.0" }
}

Declare the supported Paseo range and keep it current when adopting newer APIs. See the requirements contract, including legacy manifests and prerelease matching.

The config key is the runtime plugin ID. The manifest ID is the default selected during install; --id overrides it. Existing configuration is not renamed when the manifest changes, and the runtime does not compare the two IDs. The same directory can be installed under several config keys.

Never enable plugins on a user's behalf without explicit permission. Before asking, check the target daemon's current pluginsEnabled value. State that plugins are trusted, unsandboxed code: backend code can access the daemon machine, while client contributions run inside the Paseo app.

Source changes are explicit. Run paseo plugin reload <id> to stop and fully tear down the old plugin before compiling and starting from disk. A failed reload stays failed; Paseo does not restore the old code. Use enable, disable, and remove to manage one plugin. Removing a directory source never deletes it. The global pluginsEnabled switch remains available.

Built-in plugins

Built-in plugins ship from plugins/<id>/, with paseo-plugin.json, index.server.ts, server/, and optional client entry and icon. Add the plugin ID to builtinPlugins in packages/server/src/server/plugins/builtin/index.ts; the workspace, build copy, and CI checks cover that registry. Unlisted directories do not load.

Desktop packaging ships the entire built-in plugin directory as an external resource, including declarations. The external esbuild compiler cannot read Electron's app.asar filesystem, and packaging dependencies excludes .d.ts files needed for import validation. Built-ins can import only host modules (@getpaseo/plugin/*, zod) and Node built-ins: outside the archive, nothing resolves an npm dependency, and the dist build test cannot catch one because it resolves through the repository's node_modules. The packaged-app smoke check requires every listed built-in to start without relying on account credentials.

Built-ins run in process and remain active independently of pluginsEnabled. They are absent from the installed plugin list and source configuration; their client bundles appear in the plugin catalog. Editing one in development requires a daemon restart. Directory, Git, and npm installs cannot use a built-in ID.

Provider plugins use separate installation and provider IDs. muse-provider registers the selectable muse provider (Muse Code) and a usage source. Its status({ launch }) reports availability and a diagnostic after the daemon resolves the executable. Configure command, environment, or enablement overrides under agents.providers.muse. Omit extends to keep the bundled integration; an entry with extends shadows it with a custom provider. See provider contributions for the contract and Muse Code for setup, per-agent options, and version limitations.

Install from a registry

paseo plugin add owner/slug installs the registry's reviewed artifact by default. Browse published plugins at paseo.sh/plugins. Use git:owner/repository or a full Git URL for a Git source. Registry installs keep the registry URL and ID, so update checks use its approved pin. Explicit version/ref selection is unavailable for registry installs; install an explicit source to select your own.

Registry overviews are untrusted author content, even before installation. Render them with @getpaseo/protocol/plugin-overview: no raw HTML, HTTPS-only links and images, no relative URLs, and isolated external links. The website adapter and corpus tests live in packages/website/src/plugins/overview.tsx and overview.test.tsx; the reusable corpus is packages/protocol/tests/fixtures/plugin-overview.json. A future app overview must share this policy. Installed-plugin descriptions in the app remain plain text.

Use host/owner/slug for a registry at https://host, or set PASEO_PLUGIN_REGISTRY to change the default base (including a path prefix). Private registry credentials live in daemon config under pluginRegistries: { "host": { "authorization": "Bearer token" } }. Restart your daemon after changing these startup settings. Credentials go only to the registry, never artifact hosts or redirects. Git/npm use their own host authentication.

The open registry protocol owns static hosting, record shapes, pins, and advisory install counts.

Install a Git source

GitHub repositories use git:owner/repository or github:owner/repository. Other hosts use a Git URL.

paseo plugin install git:owner/repository
paseo plugin install https://gitlab.com/group/repository.git
paseo plugin install git:owner/monorepo:plugins/review
paseo plugin install github:owner/repository --ref main

Append :relative/path for a plugin below the repository root. --ref chooses the initial branch, tag, or commit once. Updates of explicit Git sources resolve the remote's default HEAD and ask for approval. ls reports the installed commit without contacting the remote.

Managed source ownership

The public source reference owns identifier syntax and npm prerequisites; the publishing guide owns distribution. The CLI resolves directory sources before calling installPluginSource; see the public source reference for CLI and app path semantics. Only the daemon reads plugin files and acquires sources.

ManagedPluginSources owns acquisition and offline source description. Config stores the active directory; sources.json stores managed kind and the Git acquisition remote. The remote is needed because authenticated clones may have a rewritten placeholder origin. Fixed owned directory layout provides the selected subdirectory, npm package name and cleanup root. Git HEAD and the installed npm package.json checked against package-lock.json provide the current revision. Keep the complete npm dependency tree and lockfile after staging activation. No install selector governs updates.

The loader sees only the configured directory and never invokes npm. npm lifecycle scripts are disabled during acquisition; manifest preparation owns required commands before validation.

List responses retain the closed source: directory | git enum. The optional installation projection carries identity and current revision. Old npm metadata remains accepted but is no longer emitted. Installation uses features.pluginSourceInstallation; reviewed preview/apply uses features.pluginSourceUpdates, gated by the SDK and CLI entry. The old immediate-update request returns update-client guidance. Basic management remains independently available.

Preview returns exact targets and expected installed identity/root/revision. Apply validates those values, acquires the displayed artifact or commit, then rechecks state before activation. No review session is stored in the daemon. PluginService owns activation/recovery and independent bulk results.

Declare Git preparation

Most plugins should omit build. Use it only when the staged checkout must install a dependency that Paseo does not provide, generate source or assets, or perform another required preparation step:

{
  "id": "review",
  "requirements": { "paseo": ">=0.8.0" },
  "build": [
    ["npm", "ci"],
    ["npm", "run", "build"]
  ]
}

build is an optional list of argv arrays. Each array must contain at least one non-empty string; shell command strings are rejected. Paseo starts the executable directly, without a shell, from the plugin directory in the staged checkout. It never detects lockfiles or chooses a package manager.

On install and every update, Paseo resolves the exact Git revision and manifest, runs the declared commands, then validates, compiles, and activates the candidate. It logs each argv command and its output in the daemon log. If a command fails, the error includes its output, Paseo discards the candidate, and the existing installed and running version stays untouched. On a remote daemon, all of this happens on the remote daemon host.

Server contributions can write to stdout and stderr with normal Node logging. Paseo adds [paseo] entries for loading, ready, stopping, and stopped transitions. Compilation and load failures are recorded as stderr entries before a subprocess exists. Inspect the recent in-memory tail from the host plugin settings or with paseo plugin logs <id>. Git preparation commands are recorded in $PASEO_HOME/daemon.log before a plugin exists, rather than the plugin log tail. Reload, disable, and process failure retain the tail; removing the plugin clears it. Daemon restarts do not retain the tail, but structured copies remain in $PASEO_HOME/daemon.log. Plugin output can contain secrets, so do not log credentials or tokens.

Contribute behavior and UI

Default export one contribution function from each runtime entry. Keep the entries to registration wiring. Runtime code lives behind directory boundaries:

Path	Owns
index.client.tsx and client/	React, React Native, hooks, styles, surfaces, panels, and callbacks.
index.server.ts and server/	Node APIs, filesystem and process access, credentials, and handlers.
shared/	Zod RPC contracts and plain values used by both runtimes.

Do not put any other code modules in the plugin root.

Shared files import contract helpers and types from @getpaseo/plugin. Server handler files import PluginHandlerContext from @getpaseo/plugin/server. Client files import Paseo UI from @getpaseo/plugin/client/react-native. Its Icon resolves a Lucide name using the client's installed icon set; an unknown name renders nothing so it cannot break the plugin surface. Its controlled modal keeps presentation metadata on <Modal title="…" icon={…}> and body UI in <Modal.Content>. Body layout, sheet-aware scrolling, and clipboard actions follow the host UI contract. Plugin UI runs on desktop and mobile across multiple themes: color every Text from theme.colors.foreground or theme.colors.foregroundMuted, and size layout from layout.compact. See public-docs/plugins/reference.md.

SDK import boundaries

Classify every SDK export before adding it. All client entry points and implementations live under client/; all server entry points and implementations live under server/. The package root is shared code: plain data types, Zod schemas, and functions that run in both runtimes. A type-only import is still an architectural dependency; shared types must not refer to React components, hooks, Node APIs, or server contexts.

Entry	Owns	May depend on
@getpaseo/plugin	Shared data, schemas, RPC/settings definitions, runtime-neutral helpers	Shared code only
@getpaseo/plugin/server	Server contexts, lifecycle contracts, and CLI process launch	Shared and server code
@getpaseo/plugin/server/provider, /server/acp	Server provider contracts and adapters	Shared and server code
@getpaseo/plugin/client	Client contribution contexts, hooks, navigation, and UI contribution types	Shared and client code
@getpaseo/plugin/client/react-native, /client/ui	Host-provided UI components	Shared and client code
@getpaseo/plugin/client/host	App-owned rendering integration; not a plugin-author entry	Shared and client code

Server code imports shared helpers from the root and server capabilities from /server. Client code imports shared helpers from the root and client capabilities from /client. Neither runtime imports the other. Re-exports follow the same rule; tree shaking does not establish a boundary. React, React Native, JSX runtimes, and client hooks must never be reachable from the root or any server entry. Node and platform-specific code must never be reachable from the shared root.

The SDK boundary checks and real plugin-subprocess tests enforce these rules. Every SDK change must preserve them and update the public reference, migration guide, scaffold, and examples when an author-facing import changes. The plugin compiler enforces the same runtime entry rules for plugin-authored code. Keep the package export map and host-provided module maps consistent.

The compiler rejects imports across runtime directories or SDK entries, React dependencies in server code, and Node imports in client code (including bare names such as fs). Shared modules cannot import runtime-owned modules. Forbidden imports fail compilation; never replace them with empty module stubs. A relative import to any other code file in the plugin root is also rejected; move it into client/, server/, or shared/. These are compile errors naming the importing file and boundary rule. Top-level React Native calls such as StyleSheet.create belong in client/.

The scaffold omits "DOM" from tsconfig.json and does not use /// <reference lib="dom" />, so browser globals are not available across the plugin. Put sanctioned web-only APIs in client/web.ts, declare only the globals that module uses, gate each export with Platform.OS === "web", and provide a native implementation or no-op. See the public plugin reference for the complete pattern.

// index.server.ts
import type { PluginServerContext } from "@getpaseo/plugin/server";
import { createGreeting } from "./server/greeting";
import { greetRpc } from "./shared/greeting";

export default function contribute(server: PluginServerContext) {
  server.handle(greetRpc, createGreeting);
  return () => {};
}

// index.client.tsx
import type { PluginClientContext, PluginSidebarItemProps } from "@getpaseo/plugin/client";
import { SidebarRow } from "@getpaseo/plugin/client/ui";
import { Greeting } from "./client/greeting";

function GreetingItem({ currentScreen, openScreen }: PluginSidebarItemProps) {
  return (
    <SidebarRow
      icon="MessageCircle"
      active={currentScreen?.screenId === "main"}
      onPress={() => openScreen({ screenId: "main" })}
    />
  );
}

export default function contribute(client: PluginClientContext) {
  client.addScreen({ id: "main", title: "Greeting", Component: Greeting });
  client.addSidebarHeaderItem({ id: "main", title: "Greeting", Component: GreetingItem });
  return () => {};
}

The contribution function must return cleanup. Server cleanup may be async; Paseo waits for it when the plugin is reloaded, disabled, removed, disconnected, or shut down. Cleanup is for resources created by plugin code. Paseo removes registered contributions, unmounts surfaces, clears query state, rejects pending RPCs, closes the plugin's daemon session, and stops the subprocess. Cleanup errors are logged and do not interrupt host teardown.

Paseo owns the route, screen header, Lucide icon validation, close action, theme DTO, layout facts, and render error boundary. The contributed component owns the complete body below the header. The plugin owns the header's text through the screen's title (resolvePluginScreenTitle in plugins/surface-contribution.ts). A legacy addSidebarItem route (/sidebar/<id>) shows the item's title and icon instead, as before screens had titles; the addSurface alias titles its screen with the id. A /sidebar/<id> route with no legacy item of that id opens the screen with that id, so links saved before a plugin migrated keep working.

Screen params ride in the screen route's query string (plugins/routes.ts), not in app state, so reload, history, links, and the host switcher keep them without a store. Expo Router merges the route's segments (serverId, pluginId, ...) into the same search params as the query, so param keys are stored under a param. prefix; plugins never see it and may use any key. openScreen validates its input once (parsePluginOpenScreenInput); code past it trusts the params.

RPC contracts validate inputs and outputs in both the app and plugin subprocess. useRpc returns a typed async function. Use the host-provided @tanstack/react-query for request state and caching; Paseo gives each plugin installation its own query client.

usePaseo() and the handler's { paseo } context expose the same PaseoApi: projects, workspaces, agents, terminals, providers, and daemon config. They do not expose connection lifecycle.

usePaseo() is the plugin's one client: InstalledPlugin.paseo, created with the installation in packages/app/src/plugins/registry.ts over the host's existing connection and passed to setup as client.paseo. Authors release their subscriptions in their own cleanup, and teardown (disable, reload, removal, host removal) disposes the client, which ends the rest; nothing is created or disposed per mounted surface. See the public example. Switching the screen's host changes both usePaseo() and useRpc() to that host's installation. An offline selected host fails there and never falls through to another installation. A server handler owns an IPC-backed daemon session for the life of its subprocess. Use plugin RPC for plugin-specific backend behavior that is not a normal Paseo operation.

Host-targeted clients and discovery are owned by packages/app/src/plugins/hosts, with per-installation bindings supplied by the bundle loader. Bind the imperative getter to that installation; do not resolve ownership through a mutable current-plugin global. Keep observation ownership in this module and transport ownership in the app host runtime. See the public host API contract.

Each subprocess gets an exclusively owned plugin:<id> session. That identity is reserved from normal clients, never resumes another session, and is cleaned immediately on exit without reconnect grace. During daemon startup, plugin sessions may connect while application WebSockets remain paused; the daemon accepts clients only after configured plugins have settled and the initial catalog is complete.

When the same plugin contribution exists on multiple hosts, Paseo shows it once in the sidebar and adds a host picker to the screen header. The selected host supplies the bundle, RPC transport, and query cache. Explicit SDK targets follow the host API contract.

Workspace panels, Command Center items, and client slash commands are client contributions. The daemon transports their compiled bundle without interpreting placement or callbacks. Panel props contain workspace and agent IDs. Required-selector hooks read normalized client state synchronously and use shallow equality, so a panel does not subscribe to fields it does not render. Command callbacks materialize their snapshots only when invoked. Contribution discovery and panel opening never fetch active context through plugin RPC. Snapshot DTOs are deeply readonly and frozen at runtime so plugin code cannot mutate normalized app state or a memoized selection. Panels use one persisted plugin workspace-tab target, so reload, disable, removal, and restoration resolve through the current installed-plugin catalog. A missing contribution renders unavailable inside the tab. Panels declare locations: ["workspace", "explorer"] to opt into Explorer hosting; omission means workspace only. Location controls hosting, not context. An agent panel target keeps its agentId when moved between hosts. Explorer configuration can create workspace-context panels and remove existing agent-context instances, but it cannot create an agent panel without an agent-aware command.

Command Center callbacks use the selected host's existing PaseoApi for normal Paseo operations. They use typed plugin RPC only for plugin-specific backend work. Surface and panel navigation belongs to the app; plugins do not receive Expo Router or workspace-layout store access. See the public navigation fields and external links and workspace browsers for the author-facing contract.

Lifecycle hooks

Server entries register lifecycle observers with server.on() and request transforms with server.before(). The public reference owns callback shapes, ordering, and failure behavior. plugin-examples/lifecycle-logger registers all eleven hooks; plugin-examples/lifecycle-actions demonstrates common automation callbacks.

Emit from the operation owner, not a client subscription. Provider history replay must not trigger live hooks. Observers must not be awaited inside agent mutations: a callback can send a prompt or answer a permission through its own daemon session. Awaiting it there deadlocks that command.

Contribute a provider

Register a provider from index.server.ts. The provider connection is callback-based and owns all of its sessions; plugin RPC is not part of the provider data path.

import type { PluginServerContext } from "@getpaseo/plugin/server";
import type { ProviderRegistration } from "@getpaseo/plugin/server/provider";
import { createProvider } from "./server/provider";

export default function contribute(server: PluginServerContext) {
  server.registerProvider(createProvider() satisfies ProviderRegistration);
  return () => {};
}

Declare command: ["agent", "serve"] when your provider launches an executable. The daemon applies agents.providers.<id>.command and env, resolves the executable against the effective PATH, and removes parent-session and daemon-control environment variables. connect({ launch }) receives { command, args, env }: an executable path, effective arguments, and the complete sanitized environment. Spawn with those values; do not merge the plugin process's environment back in. The launch travels as data through the same provider protocol for built-in and subprocess plugins. Without a declared command, existing providers keep their connection behavior and receive no launch.

Implement optional status({ launch }) to check credentials, versions, or other prerequisites using that effective launch. Return { available: true } or { available: false, diagnostic: "Run agent login" }. The daemon checks executable availability before calling status; it exposes your diagnostic through the normal provider diagnostic command. A command-backed provider without status is available when its executable resolves. Providers with neither command nor status retain connection-based availability.

A same-ID config entry without extends overrides the plugin's enabled, command, env, label, description, and model configuration through the normal provider registry. enabled: false disables selection and discovery. An entry with extends defines the user's own provider, shadows the plugin, and logs a warning. Overrides validate before plugins load; an override for an absent plugin stays inactive and logs a warning naming the unmatched ID after built-in and configured plugin startup settles (including disabled plugins), then on each installed registry generation. Use IDs matching /^[a-z][a-z0-9-]*$/ for configurable providers. Dots and underscores remain valid for plugin registration but cannot be used as config provider IDs.

Provider config changes rebuild the affected registry entry and invalidate its catalogue; the next connection receives the new launch without restarting the daemon. Running sessions keep their current launch until refreshed, as native providers do.

Implement optional ProviderRegistration.getCatalogCacheKey(options) to share equivalent catalogue probes. The callback runs in the plugin process before discovery and receives the actual global or workspace target plus the resolved launch when a command is declared. Return a key covering effective configuration and execution environment, or undefined for target-specific caching. Ignore force when choosing identity. Existing providers need no change. See catalogue ownership.

send() resolves after acceptance. Publish operation completion, prompt disposition, turn state, configuration, permissions, persistence, and complete timeline snapshots through onEvent(). Route messages, structured commands, steering, and command side effects through session.prompt. Provider settings are toggle/select data that Paseo renders in the composer. Keep private options in the opaque ProviderSessionConfig.providerOptions object on session.open. It contains the provider defaults and per-agent overrides merged by the daemon. Validate and apply it inside the provider; core does not know your option shape. See provider options for configuration and merge semantics.

Agent refresh closes the current provider session and opens it again with current configuration and persistence. Re-read credentials and provider-owned configuration on session.open; consume the daemon launch from connect and the per-session env and MCP servers from session.open. There is no provider reload input.

For an ACP command, register runAcpProvider({ id, label, command }) from @getpaseo/plugin/server/acp. Its transformer hooks cover narrow vendor differences; do not translate the whole provider event stream. The shim uses the resolved launch for every probe and session, overlaying only the supplied per-session env for sessions. The direct and ACP examples live in plugin-examples/provider-direct and plugin-examples/provider-acp-transformer.

Provider-emitted plugin timeline items use the same renderer registration as transformed and daemon-appended plugin items. The direct example includes both sides. The renderer-only plugin-examples/inline-thinking example shows that timeline presentation remains independent of a provider implementation. The public provider plugin guide owns author workflow, lifecycle, testing, and distribution guidance.

ProviderRegistration.icon is a file path relative to the plugin directory, such as icon.svg. It must resolve inside that directory to a regular SVG file no larger than 64 KiB. The SVG must be self-contained: scripts, styles, foreignObject, event-handler attributes, JavaScript URLs, and external href or xlink:href references are rejected. Fragment references such as #mark are allowed. Paseo reads and sanitizes the file when the plugin starts; the string is never an inline SVG or URL.

Usage sources

Register a usage source from index.server.ts with server.registerUsageSource(). Import UsageSourceRegistration and normalization helpers from @getpaseo/plugin/server/usage. The plugin owns account discovery, harness labels, and credential-store reads; the daemon owns account grouping and the fetch cache. Agent popovers use only the agent's own login. The host-wide Usage modal falls back across an account's logins; any success shows usage only, and all failures show every login's labeled error and remedy. Follow the usage source discovery contract. The resolved launch environment crosses into the trusted, unsandboxed plugin subprocess for session discovery. Usage queries never run lifecycle hooks. Inputs are validated in the plugin process and remain daemon-side. icon uses the same sanitized SVG file rules as provider icons.

The daemon calls discovery for usage.list_reports; the client gates this RPC on server_info.features.usageSources. The old provider.usage.list RPC maps discovered reports for older clients.

Contribute sidebar items

Sidebar header and footer items are plugin components, not descriptors. The public reference owns the author API. The host lives in packages/app/src/plugins/sidebar-items/; packages/app/src/sidebar-nav/model.ts resolves one section's order from built-ins, plugin groups, and the section's preference (sidebarNavItems or sidebarFooterItems).

• The item's Component renders directly in the section, with no wrapper, so a fragment or array of rows lays out like separate items while Settings keeps one entry for the block. Footer items are rows between Add project and the footer's icon row. The icon row (Hosts, Help and support, Settings) is fixed app code, not a contribution slot, so the kit has no icon button.
• openPopover opens through the same PluginPopoverSurface as header buttons (plugins/popover.tsx). Any press inside a SidebarRow, including its trailing content, moves the menu anchor to that row: a capture-phase onStartShouldSetResponderCapture runs before the pressed child claims the touch on native and web, and returns false. Keyboard activation skips the responder system, so the row's own press anchors too. Until a press, the first mounted row holds the anchor. An item that renders no kit component anchors to its section container.
• SidebarSeparator reuses the app's separator and cancels the footer's horizontal padding, so the line runs edge to edge in both sections.
• SidebarRow.trailing sits in a second Pressable beside the row's button, since web cannot nest buttons. Its onPress is the row's, so a press on non-interactive trailing content presses the row; a button inside it wins its own press because only the innermost pressable responds.
• A new-API item renders from the current route's host, else the host remembered under pluginScreensHostKey(pluginId), which the screen's host switcher and the item's openScreen set. One key per plugin: switching host on any of its screens moves all its items.
• addSurface, openSurface, and addSidebarItem are undocumented aliases, tagged COMPAT(pluginSidebarAliases). addSidebarItem is recorded only in legacySidebarItems and groups as a legacy sidebar group, which the app draws as its own row: its registered icon, in the sidebar and in Settings > Sidebar, opening /plugin/<id>/sidebar/<item> on the host it remembers under its own key. It shares header ids and the plugin:<pluginId>:<id> settings key with new-API items.

Contribute buttons

Header buttons and composer pills share the client-only descriptor and registration lifecycle in packages/app/src/plugins/buttons/. The public button reference owns the author API and placement rules. Keep presentation policy in this module so another placement can reuse behavior without copying registration or action state.

Native sheets teleport their children. Button surfaces rebuild the installation's SDK, state, query, and toast providers inside the surface content, including overflow pages from different plugins. Providers only around the trigger do not reach those bodies.

Request observation with client.paseo.agents.list({ subscribe: {} }) and consume the returned subscription handle. Plain list() and agent/workspace directory .subscribe(handler) listeners create no daemon demand. Provider and project subscribe() calls establish their own demand. On capable daemons, each list-and-subscribe call has its own server ID, even for the same query. Older daemons retain shared delivery behavior. Handle snapshots also run after reconnect; replace your view before applying its subsequent updates. The installation owns every observation created through its API and releases them on unload, including setup failure. 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.

Contribute timeline items

Timeline transformers and renderers are client contributions. The daemon's canonical rows and built-in projection stay unchanged. The app transforms each source item while building the render model, for both fetched history and live events, before native Markdown splitting and Overview tool grouping. Assistant callbacks receive the accumulated source text, never display fragments. Live assistant messages use phase: "streaming"; committing to history makes them "complete". Paseo memoizes by source-item reference and phase and derives replacement IDs from source identity, so streaming updates preserve mounted component identity.

query.itemType selects one public AgentTimelineItem.type. The callback owns any detailed recognition and returns plain plugin item objects. undefined keeps the source item, items replaces it, and an empty array removes it. Output data must be JSON-compatible. Paseo adds the runtime plugin ID, preserves the source timeline cursor and identity, validates renderer data with its Zod schema, and mounts the component inside the normal plugin runtime and error boundary. An optional output id distinguishes several stable replacements from the same source item; its output index is the default.

Transformers run synchronously and must be deterministic. When several transformers match, the first one that returns a result owns that source item. Plugin and registration ordering is stable. See plugin-examples/timeline-items for the complete contract.

A plugin subprocess can also append a canonical plugin row from a server handler:

await paseo.agents.ref(agentId).timeline.append({
  type: "plugin",
  id: "review",
  kind: "review-result",
  version: 1,
  data: { status: "ready" },
});

The daemon stamps the runtime pluginId; plugin code never supplies it. Reusing the same id replaces the previous row from that plugin on live clients and fresh timeline fetches. Rows live in the daemon's in-memory timeline and survive scroll, refetch, and reconnect, but not a daemon restart. A row without an installed renderer shows an unavailable placeholder. Serialized data must be at most 64 KiB; the daemon rejects a larger append instead of storing a payload that cannot be rendered intact. The daemon advertises this RPC through server_info.features.pluginTimelineItems.

Contribute client slash commands

addSlashCommand registers an agent- or workspace-context command in the composer. The callback runs in the app, receives the trimmed text after the command name as args, and receives the same paseo, rpc, openScreen, workspace, agent, and openPanel capabilities as the matching Command Center callback.

client.addSlashCommand({
  name: "review",
  description: "Run the review bot",
  argumentHint: "[scope]",
  context: "agent",
  async onSubmit({ args, agent, rpc }) {
    await rpc(startReview, { agentId: agent.id, scope: args });
  },
});

Paseo owns the autocomplete row, input clearing, and error toast. It never sends the command text to the agent. Built-in client commands win name and alias collisions, plugin commands win provider-command collisions, and the first plugin in stable catalog order wins collisions between plugins. Plugin slash commands do not run when the composer has attachments.

Contribute composer attachments

Register a declarative attachment source backed by a plugin RPC. Paseo owns the attachment menu, search picker, drafts, selected pill, and submission. The plugin returns complete text snapshots; credentials and vendor API calls stay in the daemon handler.

// index.server.ts
import type { PluginServerContext } from "@getpaseo/plugin/server";
import { search } from "./server/issues";
import { searchIssues } from "./shared/issues";

export default function contribute(server: PluginServerContext) {
  server.handle(searchIssues, search);
  return () => {};
}

// index.client.tsx
import type { PluginClientContext } from "@getpaseo/plugin/client";
import { issues } from "./shared/issues";

export default function contribute(client: PluginClientContext) {
  client.addAttachmentSource(issues);
  return () => {};
}

Attachment sources stay scoped to the composer's host. Unlike sidebar contributions, equal sources on several hosts are not coalesced. The selected snapshot submits as a text attachment with neutral external-resource presentation, so it remains readable if the plugin is removed or an older peer drops the optional presentation fields.

Contribute settings

Register ordinary components with client.addSettingsScreen and open them with openSettings. The host settings shell owns navigation and layout; plugin content must not add another page scroll view or header. See the author contract and plugin-examples/settings for the named UI components and persistence API.

Settings storage is scoped to the runtime installation ID, never the source path or manifest ID. Its writer lives with the plugin subprocess, while its directory lives outside managed sources, so updates and reloads retain values. Settings-change notifications must not enter the catalog reload path: that path disposes the plugin and would destroy open drafts after every save.

server.registerSettings(definition) returns a server-side handle. Use read() for the current ready or invalid state and subscribe() for successful saves, resets, and migrations. The subscription cleanup belongs in the plugin's contribution cleanup when it outlives the entry.

Contribute a theme

addTheme takes a small light or dark palette and a display name. Paseo expands it through the same semantic builders as the built-in themes, so plugins do not depend on the complete app token contract. Unistyles needs every theme name at StyleSheet.configure time, so packages/app/src/styles/theme.ts reserves one light and one dark plugin slot. The appearance provider rewrites the matching slot when the selection changes. See unistyles.md for the runtime-patching rules the appearance settings share.

addTheme is a client registration and belongs in index.client.tsx. A client that predates it cannot evaluate that entry. Daemons advertise features.pluginThemes in server_info; the plugin theme catalog is the one place the app reads it, and a host without it contributes no themes.

The selection persists as theme: "plugin" plus a pluginThemeId of <pluginId>/theme/<themeId>, so equal themes on several hosts coalesce the way sidebar contributions do. Two hosts can answer that id with different palettes, so picking a theme records its host through rememberPluginContributionHost and resolution prefers it; a peer connecting or dropping then does not repaint the app. Without a preference the sorted registry snapshot decides, so the result is stable rather than arrival-ordered. The app resolves that id against the installed catalog on every change; an id nothing contributes falls back to the default preference instead of painting the reserved slot's placeholder colors.

Existing plugin authors should follow the standalone v0.8 runtime-entry migration guide.

See plugin-examples/local-plugin for a native surface, plugin-examples/linear for a complete attachment-source example, plugin-examples/timeline-items for timeline projection, and plugin-examples/catppuccin for a theme.