paseo/docs/providers.md

Adding a New Provider to Paseo

This guide walks through adding a new agent provider end-to-end. There are two integration patterns, and this doc covers both.

Provider-native session options

AgentSessionConfig.providerOptions carries JSON-safe configuration for the selected provider. The names and nesting are the provider's native contract; options are not portable between providers. Paseo validates the object with the selected provider's strict schema before constructing a session. Unknown keys fail with their providerOptions.* path. Paseo-owned controls such as cwd, model, prompt, environment, session identity, MCP transport, callbacks, and hooks cannot be passed here.

This Paseo version accepts these keys:

• Codex: approval_policy, sandbox_mode, sandbox_workspace_write.{writable_roots,network_access,exclude_slash_tmp,exclude_tmpdir_env_var}, web_search, features.multi_agent_v2, and features.network_proxy. A network proxy object may contain enabled, proxy_url, socks_url, enable_socks5, enable_socks5_udp, allow_local_binding, allow_upstream_proxy, dangerously_allow_all_unix_sockets, dangerously_allow_non_loopback_proxy, domains, and unix_sockets. See the Codex configuration reference.
• Claude: allowedTools, disallowedTools, additionalDirectories, sandbox, and settings. The accepted sandbox fields cover enablement, fail-if-unavailable behavior, excluded and unsandboxed commands, filesystem read/write rules, network domain/socket/local-binding rules, weaker nested sandboxing, ignored violations, and the ripgrep command. settings accepts native permissions.{allow,ask,deny} and sandbox settings. See the Claude Agent SDK TypeScript reference and Claude settings reference.
• OpenCode: permission, either one ask/allow/deny action or the native per-tool rule object. Supported entries are read, edit, glob, grep, list, bash, task, external_directory, todowrite, question, webfetch, websearch, codesearch, repo_clone, repo_overview, lsp, doom_loop, and skill. See the OpenCode permissions reference. OpenCode permissions are application policy, not an OS sandbox.

Each provider definition owns its option schema and exact MCP preapproval mapping. A new provider must fail closed for Hub unattended execution until it can approve one exact injected MCP server and tool identity without approving native tools.

Two Integration Patterns

ACP (Agent Client Protocol) -- recommended

Extend ACPAgentClient from packages/server/src/server/agent/providers/acp-agent.ts. The base class handles process spawning, stdio transport, session lifecycle, streaming, permissions, and model discovery. You provide configuration (command, modes, capabilities) and optionally override isAvailable() for auth checks.

The only built-in ACP provider today is copilot (copilot-acp-agent.ts). GenericACPAgentClient (generic-acp-agent.ts) is also ACP-based but is used for user-defined custom providers configured via extends: "acp" overrides — see docs/custom-providers.md.

Copilot custom agents are exposed through ACP session config, not the slash-command list. When custom agents are available, Copilot returns a select config option with id: "agent" and category: "_agent"; Paseo maps that to the agent provider feature. Copilot uses the agent display name as the option value, and the blank value means the default Copilot agent.

ACP permission options are rendered as ordered actions and Paseo returns the selected option's exact optionId. Agents can therefore encode a single-choice question as multiple options of the same allow kind. Auto-accept does not resolve those chooser requests; they always wait for the user.

ACP shims can own model discovery through catalogModelResolver; the shared client owns the probe process and refresh deadline. Keep vendor RPCs in the shim. Cursor uses cursor/list_available_models because switching models during discovery writes its saved CLI preferences and selection history. Cursor versions without that extension must be updated. Kimi still probes model selections in its own shim. The initial session supplies modes and the current model; it does not override the model list returned by a resolver.

Direct

Implement the AgentClient and AgentSession interfaces from agent-sdk-types.ts yourself. This gives full control but requires you to handle process management, streaming, permissions, and session persistence from scratch.

Existing direct providers: claude (in providers/claude/agent.ts), codex (codex-app-server-agent.ts), opencode (opencode-agent.ts), pi (providers/pi/agent.ts), and omp (providers/omp/agent.ts). The dev-only mock provider (mock-load-test-agent.ts) is also direct.

Claude first-party model metadata lives in packages/server/src/server/agent/providers/claude/model-manifest.ts. When adding or updating a Claude model, update that manifest only; the model picker thinking options and Claude-specific feature gates are derived from the manifest. Do not add model-specific Claude capability lists in feature code.

Paseo tools are not implemented as MCP tools internally. They live in a shared tool catalog under packages/server/src/server/agent/tools/; MCP is only the fallback adapter. The daemon resolves agents.providers.<provider>.paseoTools by the exact provider ID. The catalog policy belongs to the caller: it filters the tools exposed to the current agent. When that agent calls create_agent, the child receives the policy for the child provider ID; the caller's policy is not inherited.

A provider that can register runtime tools directly should set supportsNativePaseoTools: true and consume the already-filtered launchContext.paseoTools in createSession/resumeSession. When native tools are present, AgentManager strips the internal Paseo MCP server from the provider launch config so the provider does not receive the same tools twice. Providers that only know MCP should keep supportsMcpServers: true and let the daemon inject /mcp/agents; the MCP server builds the same policy-filtered catalog for that caller. Filtering is enforced at catalog registration in both paths. Browser tools remain subject to the daemon browser-tools setting and browser-host availability.

Pi is a process-backed provider. Paseo requires the user to have the pi binary installed and talks to it through pi --mode rpc; the server package does not embed Pi's SDK/runtime packages.

Paseo's per-agent and daemon-wide system prompts are appended by its generated Pi integration extension. Paseo deliberately does not pass --append-system-prompt, because that flag replaces Pi's automatic APPEND_SYSTEM.md discovery instead of composing with it.

Pi model records expose input capabilities through model.input. Only send raw RPC images when the current model explicitly includes "image" in that list. Text-only Pi/OMP models reject image content and persist the rejected image in JSONL history, so image prompts for those models must be materialized to a local file and passed as a text path hint instead.

Pi MCP support depends on the open-source pi-mcp-adapter extension being loaded for the agent cwd. Probe with Pi RPC get_commands; the adapter registers an extension command named mcp (often with sourceInfo.source containing pi-mcp-adapter). When Paseo injects MCP servers into Pi, write a per-agent MCP config and pass it with --mcp-config instead of modifying user or project MCP files. Because that flag replaces the Pi global config layer, preserve the existing <Pi agent dir>/mcp.json in the generated file before overlaying injected servers. For local HTTP servers such as Paseo's own /mcp/agents endpoint, explicitly disable adapter OAuth (auth: false, oauth: false) in the generated config.

Pi control-plane RPCs wait 60 seconds by default. Override params.rpcTimeoutMs when extension or MCP startup on a slow host needs more time. Timeout errors name the pending RPC phase and report both elapsed time and the configured deadline. This setting does not govern long-running Pi compaction or Pi extension UI results. See OMP profiles and Pi-compatible forks for OMP startup and RPC deadlines.

Pi import discovery reads Pi's persisted JSONL session files because Pi RPC does not expose a recent-session listing command. Resume and full history hydration still go through pi --mode rpc using the session file as nativeHandle.

OMP is a first-class built-in provider, disabled by default. Its launch contract, typed runtime, agent/session behavior, history, permissions, imports, and test fake live under providers/omp/; only the provider-neutral JSONL child-process transport is shared with Pi. It launches omp --mode rpc-ui, uses OMP's get_available_commands RPC for slash-command discovery, bridges OMP rpc-ui approval dialogs into Paseo permissions, and imports terminal-started sessions from ~/.omp/agent/sessions when enabled.

OMP supports native Paseo host tools. The adapter registers the full caller-scoped Paseo tool catalog directly with OMP, matching providers such as Claude that expose the full catalog through MCP. Serialize every OMP host definition with loadMode: "essential" so create_agent, send_agent_prompt, wait_for_agent, and related tools remain direct calls; omitting the field makes OMP mount non-built-in names under xd:// instead. OMP's provider-managed task subagents are surfaced as Paseo subagents through child_session imports; the parent keeps the subagents track while the child runtime stays owned by OMP. Custom OMP profiles should extend omp; other Pi-compatible forks can still extend pi, override command, and set params.sessionDir to their JSONL session directory.

Pi RPC extension UI dialog requests (select, input, editor, confirm) are bridged into Paseo question permissions and answered with extension_ui_response. Pi extensions such as ask_user may chain dialogs: for example, a select can be followed by an optional-comment input. When an ask_user tool call declares allowComment: true, Paseo presents the selection and optional comment as one question permission, answers Pi's initial select immediately, then auto-answers the follow-up optional input with the comment the user already supplied (or an empty string). Preserve placeholders and optional/skip semantics for standalone optional inputs so the app can still distinguish "skip this optional input" from "cancel the whole dialog." Fire-and-forget extension UI requests such as notifications are intentionally ignored by the provider adapter unless Paseo grows first-class UI for them.

OpenCode 1 keeps MCP and process environment outside the session boundary. Paseo shares one OpenCode server for ordinary agents and installs a daemon-owned plugin through OPENCODE_CONFIG_CONTENT. The plugin reads the exact agent environment and caller-scoped Paseo tool catalog from the daemon's private loopback bridge for each OpenCode session. Bridge context lives only in daemon memory and is removed when the Paseo session closes. The content-addressed plugin artifact contains no session data or secrets.

An agent with custom environment variables or user-configured MCP servers gets a dedicated OpenCode server. Keep that isolation until OpenCode exposes those values as session-owned configuration. Configure custom MCP with mcp.add; do not follow it with mcp.connect, which only toggles config-backed servers.

OpenCode owns user message IDs. Do not pass Paseo-generated IDs to OpenCode prompt APIs; let OpenCode create msg* IDs and record the user timeline item from the message.updated event.

AgentManager owns the one canonical timeline row for a foreground prompt carrying a Paseo clientMessageId. It records that row when startTurn accepts, with the wire messageId set to the same value. Provider adapters still emit their native user-message echo with the same clientMessageId when available; the manager records its provider identity on the internal row without changing or redispatching the wire item. If an adapter emits the echo before startTurn resolves, the manager records the provider identity with the row at acceptance. Provider adapters continue to own externally initiated user rows that have no Paseo client identity. Do not perform global transcript text dedupe.

Active-turn steering is an optional AgentSession.steerActiveTurn operation. The manager owns admission against its exact foreground turn, canonical user-message creation, echo reconciliation, and falls back to the normal interrupt-and-replace path only when the adapter reports unavailable. An adapter error leaves the steer's fate ambiguous and must surface without an interrupt or retry. Codex calls turn/steer with the native expected turn and Paseo client user-message ID. Claude pushes an admitted steer into the exact active SDK query input; isolated control commands remain unavailable. OpenCode calls session/prompt_async with an OpenCode-generated message ID; the server queues the prompt while busy and the next LLM call in the same Paseo turn includes it. Pi sends its native steer RPC, which queues the message for delivery after the in-flight assistant turn's tool calls. Slash-command inputs report unavailable because pi rejects extension commands on the steer path, and echo identity is correlated by message text because pi's steer RPC takes no message ID. A missing session reports unavailable and uses the normal interrupt fallback.

A steering adapter also owes its interrupt: stopping a turn must discard the steers the provider has not read yet, or one of them resumes the turn the user just stopped. Codex clears pending input when it aborts a turn; Claude does not, so its adapter cancels the SDK messages it queued before calling query.interrupt(). Pi requires clear_queue before abort; older binaries without that RPC retain their native queue behavior until the pi compatibility floor reaches 0.84.4.

SteerActiveTurnOptions.clearPendingPermissions makes permission release part of the provider contract. A provider that accepts such a steer queues it first, denies permissions blocking its delivery, and stops once the steer is read. Steers without the flag leave permissions open. A denied plan remains in the timeline because the pending card was the only other copy of its text.

Rewind accepts the canonical wire messageId and resolves it to the provider identity before calling the adapter. A submitted prompt cannot be rewound until its provider echo supplies that identity.

Submitted user-message wire items carry the same Paseo ID in messageId and clientMessageId. Provider adapters attach clientMessageId only to the echo for that foreground submission; provider history and externally initiated user rows do not have a Paseo client ID.

Provider adapters must terminalize every transient timeline row before emitting the turn's terminal event. Codex may omit the completed contextCompaction item when a turn ends during compaction, so its adapter closes any pending root compaction before forwarding turn_completed, turn_failed, or turn_canceled. A terminal turn must never leave the client showing an operation as still loading.

Draft metadata lookups should avoid creating provider sessions when the upstream provider has top-level APIs for that metadata. Prefer AgentClient.fetchCatalog, listCommands, or listFeatures over creating a scratch AgentSession; scratch sessions can show up as empty native sessions in provider import/history UIs. fetchCatalog is the single discovery API for models and modes — provider implementations may use one process, separate upstream calls, or static data internally, but callers outside the provider do not get separate runtime model/mode probes. Draft command listing and scratch-session feature listing require an explicit draft model. Do not resolve a default model through catalog discovery. A client-level listFeatures implementation may return features from an incomplete, model-less draft and owns which features are valid in that state.

Provider session import has its own contract. The picker calls listImportableSessions and receives rows only: provider handle, cwd, title, prompt previews, and last activity. Import calls importSession({ providerHandleId, cwd }) for the selected row and must not call listing again. The provider returns the resumed session, storage config, persistence handle, and hydrated timeline for that one native session; AgentManager.importProviderSession seeds the daemon timeline and publishes the Paseo agent only after it is ready.

Provider Helper Processes

Provider-owned helper processes that can outlive an individual agent session must be recorded in the daemon's managed-process registry. Store provider/kind metadata, the PID, launch command/args, and process identity captured from the platform process table. Remove the record on normal exit or shutdown.

If a helper process has a readiness phase, the provider's lifecycle model must own the process immediately after spawn, before readiness succeeds. Startup timeout, startup exit, and daemon shutdown must all clean up through that owned generation. Do not keep a spawned helper only inside a readiness promise; that creates a live process outside the manager/reaper contract.

Daemon bootstrap reconciles that ledger in the background, without blocking startup: dead PIDs are deleted, PID identity mismatches are deleted without killing anything, only positively matched Paseo-owned leftovers are terminated, and a record whose process cannot be inspected is left in place for the next reconcile rather than deleted. Do not add broad process-name sweepers for provider cleanup; cleanup starts from records Paseo previously wrote.

---

Provider Snapshot Refresh Contract

Provider snapshots are views of the catalogues needed for a target. Before looking up cached results or discovery in flight, the manager calls optional AgentClient.getCatalogCacheKey(options). The provider owns equivalence: equal keys must mean the same availability, models and modes, including the effective configuration and execution environment. force does not change identity. Omitting the method or returning undefined keeps target-specific caching. Codex and Claude's current host clients share across directories; configured provider identities remain isolated.

The key chooses storage, never execution. Availability and catalogue discovery receive the actual { scope: "global", force } or { scope: "workspace", cwd, force } request, including when another target can share its result. Runtime-aware adapters must use that target for both probing and key resolution. An explicit home-directory workspace is distinct from a semantic global request. Plugin callbacks follow the same contract; see plugin providers.

ProviderSnapshotManager owns one refresh deadline per provider. The deadline starts before the availability check and covers that check plus the complete catalog probe. Providers that make multiple catalog requests must not apply this deadline separately to each request. The manager aborts the shared refresh signal at the deadline. Providers name active catalog operations and finish subprocess, server, or session cleanup before rejecting. Timeout errors list the operations that were still active when the deadline expired.

Catalogue results stay cached by identity until explicit refresh or a change to that provider's configuration. Keys are resolved on each read so project configuration can select a different cached catalogue. Selector opening may read a loading or stale query, but does not force provider probing.

Saved provider/model choices are user intent. Catalogue failure must not erase them or substitute another model. Creation reads the caller's host and directory directly; an earlier global snapshot must not settle a project form's initial selection.

The server's provider keys never cross the wire. Clients advertising provider_snapshot_references receive directory-to-hash announcements; an unknown hash uses the existing snapshot request. The manager detaches each fresh result once and publishes its content identity with the entry; readers share these values read-only. Each target keeps its published snapshot until membership, content or discovery freshness changes. All affected targets commit before subscribers run; subscriber failures are logged without changing discovery or configuration outcomes. The session compares both sides of a committed transition under the client's current visibility policy and sends only visible changes. It combines result identities with the client's encoding and icon policy, without traversing models. Reference hashes exclude freshness; legacy embedded hashes include it. Only responses that send a body compact the catalogue. Per-provider fetchedAt travels separately for reference clients and still means when discovery succeeded. generatedAt remains the time the response or announcement was generated. Refresh keeps settled entries visible until the next result, so unchanged discovery sends freshness without another model body.

The app's snapshot cache owns compact expansion and stores one body per server/hash, with separate directory/hash/freshness records under the same byte budget. Missing bodies share a React Query request; directory queries cancel superseded pulls before accepting pushes. Default SDK clients keep expanded entries and full updates. Only callers that own materialization opt into wire snapshots. Keep the full encoding for older clients; compact-snapshot support alone does not imply reference support.

Settings refresh invalidates requested providers across known targets and refreshes them in their actual execution context, so every connected client receives the refreshed view. Discovery shares work by provider key and admits at most four concurrent catalogue probes per configured provider, so a stalled provider does not block discovery for others. Configuration replacement invalidates only changed providers; unchanged entries, clients, and discovery in flight survive. Preparation leaves installed reads untouched until commit. Plugin replacement uses registration runtime identity, so unchanged registrations and builtins keep their results. Await the refresh or warmup promise for completion: equal results, including equal discovery timestamps, emit no transition.

---

Provider Usage Fetchers

Provider plan usage is fetch-on-demand, not a daemon push subscription. The app calls provider.usage.list.request through React Query when the usage tooltip or Host Usage settings screen is shown, and the daemon returns the normalized ProviderUsage list directly.

To add plan usage for a provider, add packages/server/src/services/quota-fetcher/providers/<provider>.ts and register it in packages/server/src/services/quota-fetcher/manifest.ts. The provider file exports only its fetcher class; provider auth, endpoint constants, API schemas, and normalization helpers stay private in that file. A fetcher owns provider auth/API parsing and returns the generic shape:

• providerId, displayName, status, and optional planLabel
• any number of windows such as Session, Weekly, or Biweekly
• optional balances for credits, USD, requests, or tokens
• optional details for provider-specific rows

Keep the protocol shape provider-agnostic. Do not add provider-specific renderers for new limit windows; labels and generic bars should carry the UI. API responses should be parsed and normalized with Zod inside the fetcher, while the protocol boundary stays strict so old/new client compatibility is explicit.

Kimi Code usage follows the CLI-managed credential file at KIMI_CODE_HOME or ~/.kimi-code/credentials/kimi-code.json; do not probe the legacy ~/.kimi path as the primary source for current Kimi Code installs.

Cursor usage reads the desktop state.vscdb token first, then cursor-agent's ~/.config/cursor/auth.json. Headless hosts only have the CLI file.

Usage fetchers are read-only on credentials

A fetcher reads the provider's credential file and never writes it. On a 401 or 403 it returns unavailable and leaves refresh to the provider's own CLI: redeeming a refresh token in the fetcher invalidates the CLI's copy (refresh tokens are single-use), and rewriting the file through the fetcher's Zod schema drops any field the schema does not model, corrupting the file for the CLI.

---

ACP Provider Checklist

1. Create the provider class

Create packages/server/src/server/agent/providers/{name}-agent.ts.

Define capabilities, modes, and a thin subclass of ACPAgentClient:

import type { Logger } from "pino";
import type { AgentCapabilityFlags, AgentMode } from "../agent-sdk-types.js";
import type { ProviderRuntimeSettings } from "../provider-launch-config.js";
import { ACPAgentClient } from "./acp-agent.js";

const MY_PROVIDER_CAPABILITIES: AgentCapabilityFlags = {
  supportsStreaming: true,
  supportsSessionPersistence: true,
  supportsDynamicModes: true,
  supportsMcpServers: true,
  supportsReasoningStream: true,
  supportsToolInvocations: true,
};

const MY_PROVIDER_MODES: AgentMode[] = [
  {
    id: "default",
    label: "Default",
    description: "Standard agent mode",
  },
  // Add more modes as needed
];

type MyProviderClientOptions = {
  logger: Logger;
  runtimeSettings?: ProviderRuntimeSettings;
};

export class MyProviderACPAgentClient extends ACPAgentClient {
  constructor(options: MyProviderClientOptions) {
    super({
      provider: "my-provider", // Must match the ID used everywhere else
      logger: options.logger,
      runtimeSettings: options.runtimeSettings,
      defaultCommand: ["my-agent-binary", "--acp"], // CLI command to spawn
      defaultModes: MY_PROVIDER_MODES,
      capabilities: MY_PROVIDER_CAPABILITIES,
    });
  }

  // Override isAvailable() if the provider needs specific auth/env vars
  override async isAvailable(): Promise<boolean> {
    if (!(await super.isAvailable())) {
      return false; // Binary not found
    }
    return Boolean(process.env["MY_PROVIDER_API_KEY"]);
  }
}

The super.isAvailable() call checks that the binary from defaultCommand is on $PATH. Override only to add credential checks on top.

For reference, here is how Copilot does it -- no auth override needed because the CLI handles auth itself:

export class CopilotACPAgentClient extends ACPAgentClient {
  constructor(options: CopilotACPAgentClientOptions) {
    super({
      provider: "copilot",
      logger: options.logger,
      runtimeSettings: options.runtimeSettings,
      defaultCommand: ["copilot", "--acp"],
      defaultModes: COPILOT_MODES,
      capabilities: COPILOT_CAPABILITIES,
    });
  }

  override async isAvailable(): Promise<boolean> {
    return super.isAvailable();
  }
}

2. Add to the provider manifest

In packages/server/src/server/agent/provider-manifest.ts, add mode definitions with UI metadata (icons, color tiers) and a provider definition entry.

First, define the modes with visual metadata:

const MY_PROVIDER_MODES: AgentProviderModeDefinition[] = [
  {
    id: "default",
    label: "Default",
    description: "Standard agent mode",
    icon: "ShieldCheck",
    colorTier: "safe",
  },
  {
    id: "autonomous",
    label: "Autonomous",
    description: "Runs without prompting",
    icon: "ShieldOff",
    colorTier: "dangerous",
  },
];

Available colorTier values: "safe", "moderate", "dangerous", "planning". Available icon values: "ShieldCheck", "ShieldAlert", "ShieldOff".

Then add to the AGENT_PROVIDER_DEFINITIONS array:

export const AGENT_PROVIDER_DEFINITIONS: AgentProviderDefinition[] = [
  // ... existing providers ...
  {
    id: "my-provider",
    label: "My Provider",
    description: "Short description of the provider",
    defaultModeId: "default",
    modes: MY_PROVIDER_MODES,
    // Optional: enable voice
    voice: {
      enabled: true,
      defaultModeId: "default",
      defaultModel: "some-model",
    },
  },
];

3. Add the factory to the provider registry

In packages/server/src/server/agent/provider-registry.ts, import your class and add a factory entry to PROVIDER_CLIENT_FACTORIES:

import { MyProviderACPAgentClient } from "./providers/my-provider-agent.js";

const PROVIDER_CLIENT_FACTORIES: Record<string, ProviderClientFactory> = {
  // ... existing factories ...
  "my-provider": (logger, runtimeSettings) =>
    new MyProviderACPAgentClient({
      logger,
      runtimeSettings,
    }),
};

The factory is invoked with (logger, runtimeSettings, options); options.workspaceGitService is also available if you need it (see the codex factory for an example). The registry already passes the per-provider runtime settings slice through, so you don't index into the map yourself.

4. Add a provider icon (app)

Create packages/app/src/components/icons/my-provider-icon.tsx following the pattern from existing icons (e.g., claude-icon.tsx):

import Svg, { Path } from "react-native-svg";

interface MyProviderIconProps {
  size?: number;
  color?: string;
}

export function MyProviderIcon({ size = 16, color = "currentColor" }: MyProviderIconProps) {
  return (
    <Svg width={size} height={size} viewBox="0 0 24 24" fill={color}>
      <Path d="..." />
    </Svg>
  );
}

Then register it in packages/app/src/components/provider-icons.ts by adding an entry to the existing PROVIDER_ICONS map (which already covers the built-in providers):

import { MyProviderIcon } from "@/components/icons/my-provider-icon";

const PROVIDER_ICONS: Record<string, typeof Bot> = {
  // ... existing entries ...
  "my-provider": MyProviderIcon as unknown as typeof Bot,
};

If no icon is registered, getProviderIcon() falls back to a generic Bot icon from lucide.

5. Add E2E test config

In packages/server/src/server/daemon-e2e/agent-configs.ts, add your provider:

export const agentConfigs = {
  // ... existing configs ...
  "my-provider": {
    provider: "my-provider",
    model: "default-model-id",
    modes: {
      full: "autonomous", // Mode with no permission prompts
      ask: "default", // Mode that requires permission approval
    },
  },
} as const satisfies Record<string, AgentTestConfig>;

Add an availability check in isProviderAvailable(). Note isCommandAvailable is async, so all branches await it:

case "my-provider":
  return (
    (await isCommandAvailable("my-agent-binary")) &&
    Boolean(process.env.MY_PROVIDER_API_KEY)
  );

Add to the allProviders array (current built-ins are claude, codex, copilot, opencode, pi, omp):

export const allProviders: AgentProvider[] = [
  "claude",
  "codex",
  "copilot",
  "opencode",
  "pi",
  "my-provider",
];

6. Run typecheck

npm run typecheck

This is required after every change per project rules.

---

Direct Provider Checklist

If your agent does not speak ACP, implement the interfaces from agent-sdk-types.ts directly.

Interfaces to implement

The interfaces below are abridged signatures — read agent-sdk-types.ts for the full source of truth (option bag types, generics, etc.).

AgentClient -- factory for sessions and model/mode listing:

interface AgentClient {
  readonly provider: AgentProvider;
  readonly capabilities: AgentCapabilityFlags;
  createSession(
    config: AgentSessionConfig,
    launchContext?: AgentLaunchContext,
    options?: AgentCreateSessionOptions,
  ): Promise<AgentSession>;
  resumeSession(
    handle: AgentPersistenceHandle,
    overrides?: Partial<AgentSessionConfig>,
    launchContext?: AgentLaunchContext,
  ): Promise<AgentSession>;
  fetchCatalog(options: FetchCatalogOptions): Promise<ProviderCatalog>;
  isAvailable(): Promise<boolean>;
  // Optional:
  listImportableSessions(
    options?: ListImportableSessionsOptions,
  ): Promise<ImportableProviderSession[]>;
  importSession(
    input: ImportProviderSessionInput,
    context: ImportProviderSessionContext,
  ): Promise<ImportedProviderSession>;
  getDiagnostic?(): Promise<{ diagnostic: string }>;
}

AgentSession -- a running agent conversation:

interface AgentSession {
  readonly provider: AgentProvider;
  readonly id: string | null;
  readonly capabilities: AgentCapabilityFlags;
  readonly features?: AgentFeature[];
  run(prompt: AgentPromptInput, options?: AgentRunOptions): Promise<AgentRunResult>;
  startTurn(prompt: AgentPromptInput, options?: AgentRunOptions): Promise<{ turnId: string }>;
  steerActiveTurn?(prompt: AgentPromptInput, options: SteerActiveTurnOptions): Promise<SteerResult>;
  subscribe(callback: (event: AgentStreamEvent) => void): () => void;
  streamHistory(): AsyncGenerator<AgentStreamEvent>;
  getRuntimeInfo(): Promise<AgentRuntimeInfo>;
  getAvailableModes(): Promise<AgentMode[]>;
  getCurrentMode(): Promise<string | null>;
  setMode(modeId: string): Promise<void | AgentProviderNotice>;
  getPendingPermissions(): AgentPermissionRequest[];
  respondToPermission(
    requestId: string,
    response: AgentPermissionResponse,
  ): Promise<AgentPermissionResult | void>;
  describePersistence(): AgentPersistenceHandle | null;
  interrupt(): Promise<void>;
  close(): Promise<void>;
  // Optional:
  listCommands?(): Promise<AgentSlashCommand[]>;
  setModel?(modelId: string | null): Promise<void>;
  setThinkingOption?(thinkingOptionId: string | null): Promise<void | AgentProviderNotice>;
  setFeature?(featureId: string, value: unknown): Promise<void>;
  tryHandleOutOfBand?(prompt: AgentPromptInput): {
    run(ctx: { emit: (event: AgentStreamEvent) => void }): Promise<void>;
  } | null;
}

setMode and setThinkingOption may return an AgentProviderNotice when the provider knows the change needs user-facing context. For example, providers that stage changes until the next turn should return an info notice while a turn is already running. The app renders the notice generically as a toast; provider-specific lifecycle behavior stays in the provider implementation.

Steps

1. Create packages/server/src/server/agent/providers/{name}-agent.ts implementing both interfaces
2. Add to the provider manifest (same as ACP step 2 above)
3. Add factory to the registry (same as ACP step 3 above)
4. Add icon (same as ACP step 4 above)
5. Add E2E config (same as ACP step 5 above)
6. Run typecheck

---

Testing

Manual testing with the CLI

Start the daemon if not already running, then:

# Launch an agent with your provider
paseo run --provider my-provider

# Launch with a specific model and mode
paseo run --provider my-provider --model some-model --mode default

# List running agents
paseo ls -a -g

# Check if the provider reports models
paseo models --provider my-provider

E2E test patterns

The E2E configs in agent-configs.ts expose two helpers:

• getFullAccessConfig(provider) -- returns config for a session with no permission prompts
• getAskModeConfig(provider) -- returns config for a session that triggers permission requests

Tests use isProviderAvailable(provider) to skip when the binary or credentials are missing, so CI will not fail for providers that are not installed.

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Gotchas

Mode IDs can be URIs. ACP providers like Copilot use full URIs as mode IDs (e.g., "https://agentclientprotocol.com/protocol/session-modes#agent"). Never assume mode IDs are simple strings. The manifest defaultModeId must match exactly.

Models and modes are discovered dynamically. ACP providers report available models and modes at runtime via the protocol. The static definitions in provider-manifest.ts are used for UI scaffolding (icons, color tiers) but the runtime values from the agent process are the source of truth.

AgentProvider is always string. The type alias is type AgentProvider = string. Provider IDs are validated against the manifest at runtime, not at the type level.

Auth patterns vary. Some providers need API keys in env vars (ANTHROPIC_API_KEY, OPENAI_API_KEY), some use OAuth tokens (CLAUDE_CODE_OAUTH_TOKEN), some use auth files (~/.codex/auth.json), and some handle auth entirely in their CLI binary (Copilot). Your isAvailable() method should check whatever is needed.

The manifest mode list and the agent class mode list are separate. The manifest in provider-manifest.ts includes UI metadata (icon, colorTier). The agent class defines modes without UI metadata (just id, label, description). Keep them in sync.

defaultCommand is a tuple. The first element is the binary name, the rest are default arguments. The base class uses this to find the executable and spawn the process.

Runtime settings can override the command. Users can configure custom binary paths or environment variables per provider via ProviderRuntimeSettings. Your factory in the registry should pass runtimeSettings?.["your-provider"] through to the constructor.

Session-scoped cancellation needs a stop boundary inside the provider. Some agents cancel the whole session rather than one turn — OpenCode's session.abort is the example. A cancel that is still in flight when the next run starts will kill that replacement run, which is what makes "stop, then immediately prompt again" (replaceRunning, notifyOnFinish wakes, schedules) flaky. Own this in the provider session, not in AgentManager:

• Model the stop as an explicit stopping turn-state variant carrying the canceled run's terminal and the cancellation the caller is still owed. Pressing Stop again retries the stop already in progress rather than opening a second one; never fire a detached retry, it will outlive its boundary.
• Scope the cancel settlement the way the provider scopes the cancel. If cancellation is session-scoped, so is its settlement: track it on the session, accumulating every request issued, and let it outlive the stop that issued it. A request still in flight lands on the runner whenever the server gets to it — however many stops have come and gone since. Scoping it to the current stop looks right and quietly drops older requests from the gate. Only the newest may hold the gate closed, since recovering from a failed cancel is what pressing Stop again is for.
• Gate the operations the daemon issues (prompt, slash command, summarize) on both the terminal and cancel settlement. Permission and question responses are not runner operations and must stay outside the gate, or an auto-approve deadlocks the stop. Runs the provider starts on its own — plugin or autonomous wakes — are observed, not gated: the daemon does not choose when they begin, and holding their events back does not protect them from a cancel already in flight, it only hides a run that may already be dead.
• Fail closed: if the cancel never succeeded you never proved the run stopped, so refuse new runs until the next Stop issues a fresh cancel. AgentManager already turns a rejected interrupt() into a refused cancel.
• Suppress the canceled run's residue only until its authoritative terminal. Anything the provider publishes after that terminal is a new run by construction and must take the normal live path — buffering it and replaying it later is how autonomous/plugin wakes get lost.