feat(server): add ACP registry agents

[t3dotgg]

Users can't add agents from the ACP Registry on main. That flow only exists on the Orchestrator V2 branch (#2829), which will not land soon.

This ports the registry to main and runs registry agents on the current V1 orchestrator. You can search the registry's ~40 agents (Devin, Kimi CLI, Gemini CLI, Goose, and others), add one, sign in, chat with T3 MCP tools, and remove it.

Stacked on #13784.

What changed

• Registry infra from V2. Contracts, the catalog (search, prepare, inspect, resolve, managed-binary uninstall), the probe, the runtime coordinator, the sign-in flow and sign-in state, the catalog layer, and the driver. Registered in builtInDrivers.ts; the hydration and server.ts share one catalog.
• New generic V1 adapter (provider/Layers/AcpRegistryAdapter.ts), based on the V1 Antigravity adapter with behavior ported from V2's AcpAdapterV2, AcpRegistryAdapterV2, and DevinAcp:
  • Permission requests follow the thread's runtime mode through AcpClientPolicy (Supervised asks, Auto-accept edits asks for non-edits, Auto and Full access approve).
  • Form elicitations become T3 questions, except MCP tool-approval forms, which become approvals; URL elicitations go to the coordinator and show as "Continue authentication" on the provider card.
  • Stored model, agent options, mode picks, and the Plan toggle are applied before each prompt.
  • T3 MCP through AcpT3Mcp (stdio bridge and MCP-over-ACP).
  • Devin keeps V2's per-agent exception: client terminals gated by the runtime mode, and tool titles from its metadata.
• 4 RPCs: search, prepare, uninstall managed binary, accept URL auth.
• Web: registry search and "Enter manually" in the Add provider dialog, a sign-in step after adding, the shared sign-in section on registry instances (browser, terminal, and credential methods, plus sign out), managed-file cleanup on remove, and agent icons in the pickers, sidebar, palette, and settings.
• Mobile: agent icons in the model pickers, thread rows, and environment settings.
• Docs: docs/user/providers-acp.md, linked from the index, install, and permission modes pages.

Coverage of open single-provider PRs

• #13645 Devin CLI: covered by the devin registry entry.
• #12920 Kimi Code: covered by the kimi entry for chat. That PR's text generation and swarm tool rows are not.
• #13670 Prime Agent: not in the registry, so not covered.

V2 compatibility

• Same as V2: contracts/acpRegistry.ts (+test), AcpRegistryAuth, AcpRegistryAuthenticationState, AcpRegistryCatalog layer, web AcpRegistryIcon, AcpRegistrySearchStep, ProviderAuthenticationSection, ProviderAuthTerminal, AddProviderInstanceWizardSteps (all with tests), providerInstanceDisplay, and the registry model-retention rule in ProviderRegistry.
• Small deltas:
  • AcpRegistrySupport.ts (+test): isAcpRegistryError is private (knip). A fetched registry index now serves search and prepare for 5 minutes instead of a refetch on every search, and a cached index that replaces a failed fetch counts as fresh too. Review fixes: an archive command resolves inside its staging directory before chmod; installed npm and uv commands resolve only in the managed bin directory; the install lock is refreshed every minute; install errors keep only the last 4,000 characters of stderr; and auto distribution prefers a package runner the environment has. V2 should take these changes.
  • AcpRegistryProbe.ts and AcpRegistryRuntimeCoordinator.ts: session management (list, delete, providers, logout RPC) and withSessionMutation removed. The probe and live configuration also report supportsPlanMode, which the driver uses to show Plan only for agents with a plan mode.
  • AcpRegistryDriver.ts: builds the V1 adapter, drops acpSessionManagement and the nativeSessions / configurableProviders snapshot fields, sets supportsConversationRollback: false, and hides Plan until the agent reports a plan mode. Live configuration from a past session no longer marks an unauthenticated or uninstalled agent ready (V2 should take this).
  • Contracts: ServerProvider gains only iconUrl, setup.documentationUrl, auth.action, auth.canLogout. rpc.ts gains only the 4 RPCs above.
  • ProviderWizardAuthenticationStep.tsx: waits for the new instance's snapshot before it subscribes to sign-in state. AddProviderInstanceDialog.logic.ts keeps main's step labels.
  • AddProviderInstanceDialog.tsx, ProviderSettingsPanel.tsx, ProviderInstanceCard.tsx: registry parts added to main's versions, not V2's rewrites.
• New on main only: the V1 adapter and its service shape.
• When V2 merges main: take V2's side for the shared files, re-add the session-management exports, and drop AcpRegistryAdapter.ts (Services and Layers) along with the V1 adapters. acpRegistry.ts and the registry settings schema are identical, so persisted instances carry over.

Gaps

• V2 session management (list, import, delete native sessions; configure providers; the separate logout RPC). Sign out works through the shared sign-in flow.
• Mobile has no provider settings screen on main, so adding and signing in happen on web or desktop.
• Devin subagents show as tool calls. The adapter does not advertise Devin's subagent and message-grouping capabilities.
• The Mistral Vibe retry notice and rate-limit class from V2 are not ported.
• Managed registry commands are not added to the integrated terminal's PATH, and the acp-mcp-call terminal fallback is not wired (main's agent instructions do not mention it yet).

Testing

• vp test run on the ported registry tests (support, probe, coordinator, auth, auth state, driver), the new adapter test, ProviderRegistry, ProviderInstanceRegistryLive, providerCompatibility, RpcAuthorization, and server.test: 12 files, 362 passed. The adapter test runs a real ACP mock agent over both the v1 and v2 wires: a turn with stored model and mode picks, a Supervised approval, auto-approval in Full access, a form elicitation, and T3 MCP plus Devin's client terminals.
• Web: 13 files, 306 passed (search step, icons, dialog logic and routing, settings panel, pickers, sidebar, palette). Contracts 6, client-runtime 20, mobile 13 passed.
• tsc --noEmit for contracts, client-runtime, server, web, and mobile. vp lint and vp fmt on changed files (no new warnings). knip exports for server, web, client-runtime, and contracts, plus files and dependencies.
• Not run: a real registry agent or a browser pass.

Made by Claude Opus 5.5 (1M context) in Claude Code, orchestrated from T3 Code.

🤖 Generated with Claude Code

Closes discussions

• [Feature]: Add Devin CLI support #6749
• Support Kimi Code CLI as a built-in provider #7024
• kimi #7144

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

ℹ️ No successful main baseline artifact is available yet. This run establishes the initial measurement.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	—	13.5 KiB	—	15.1 KiB	✅
Codex	Thread snapshot wire	—	7.1 KiB	—	7.3 KiB	✅
Codex	Live turn WebSocket wire	—	6.5 KiB	—	7.8 KiB	✅
Codex	Live turn WebSocket decoded	—	56.3 KiB	—	66.4 KiB	✅
Codex	Live turn messages	—	10	—	21	✅
Claude	Total thread wire	—	13.5 KiB	—	15.1 KiB	✅
Claude	Thread snapshot wire	—	7.1 KiB	—	7.3 KiB	✅
Claude	Live turn WebSocket wire	—	6.5 KiB	—	7.8 KiB	✅
Claude	Live turn WebSocket decoded	—	57.0 KiB	—	66.4 KiB	✅
Claude	Live turn messages	—	9	—	21	✅

Baseline: unavailable · PR result: c36ec3c · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 114.0 KiB
• Claude decoded thread snapshot: 114.7 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — This PR introduces a substantial production capability that installs and runs third-party ACP agents, adds authentication and permission flows, changes product defaults, and spans server, client, and public contract layers. An unresolved high-severity session-lifecycle finding further warrants human review before merge.

Not approved because:

• 1 blocking correctness issue found at or above your repo's Minimum Blocking Severity

No code changes detected at c36ec3c. Prior analysis still applies.

^{Adjust the Minimum Blocking Severity for this repo — including turning it Off — in Settings. You can add or adjust custom eligibility rules. Learn more.}

[macroscopeapp]

Correction to my Effect Service Conventions review comment on Services/AcpRegistryAdapter.ts: I overlooked that per-instance adapters in this repository intentionally use shape-only modules (for example, GrokAdapter.ts), rather than Context.Service tags. The new adapter follows that convention; please disregard my finding. I withdraw that request.

^{Posted via Macroscope — Effect Service Conventions}