[Error] unhandlederror-No activated agent with id "setup.vscode"

[vs-code-engineering]

Error Message

unhandlederror-No activated agent with id "setup.vscode"

Stack Trace

    at pTe.setRequestTools (./src/vs/workbench/contrib/chat/common/participants/chatAgents.ts:540:9)
    at NV._runFn (./src/vs/workbench/contrib/chat/common/chatService/chatServiceImpl.ts:1240:0)
    at NV._run (./src/vs/base/common/observableInternal/reactions/autorunImpl.ts:110:10)
    at NV.endUpdate (./src/vs/base/common/observableInternal/reactions/autorunImpl.ts:167:11)
    at ub.endUpdate (./src/vs/base/common/observableInternal/observables/derivedImpl.ts:281:6)
    at ub.endUpdate (./src/vs/base/common/observableInternal/observables/derivedImpl.ts:281:6)
    at ub.endUpdate (./src/vs/base/common/observableInternal/observables/derivedImpl.ts:281:6)
    at SO.finish (./src/vs/base/common/observableInternal/transaction.ts:102:12)
    at LP.set (./src/vs/base/common/observableInternal/observables/observableValue.ts:77:8)
    at h7.add (./src/vs/base/common/observableInternal/set.ts:29:13)
    at vTe.addTool (./src/vs/workbench/contrib/chat/common/tools/languageModelToolsService.ts:432:0)
    at gRt.$registerToolWithDefinition (./src/vs/workbench/api/browser/mainThreadLanguageModelTools.ts:174:17)
    at a._doInvokeHandler (./src/vs/common/rpcProtocol.ts:458:16)
    at a._invokeHandler (./src/vs/common/rpcProtocol.ts:443:31)
    at a._receiveRequest (./src/vs/common/rpcProtocol.ts:373:18)
    at a._receiveOneMessage (./src/vs/common/rpcProtocol.ts:299:9)
    at lIe.value (./src/vs/common/rpcProtocol.ts:161:56)
    at E._deliver (./src/vs/base/common/event.ts:1355:12)
    at E.fire (./src/vs/base/common/event.ts:1386:8)
    at d3.fire (./src/vs/base/parts/ipc/common/ipc.net.ts:652:18)

Raw Stack Trace (minified)

Error: No activated agent with id "setup.vscode"     at pTe.setRequestTools (out/vs/workbench/workbench.desktop.main.js:943:28954)     at NV._runFn (out/vs/workbench/workbench.desktop.main.js:3002:23083)     at NV._run (out/vs/workbench/workbench.desktop.main.js:407:6694)     at NV.endUpdate (out/vs/workbench/workbench.desktop.main.js:407:7325)     at ub.endUpdate (out/vs/workbench/workbench.desktop.main.js:407:13497)     at ub.endUpdate (out/vs/workbench/workbench.desktop.main.js:407:13497)     at ub.endUpdate (out/vs/workbench/workbench.desktop.main.js:407:13497)     at SO.finish (out/vs/workbench/workbench.desktop.main.js:406:109994)     at LP.set (out/vs/workbench/workbench.desktop.main.js:407:2882)     at h7.add (out/vs/workbench/workbench.desktop.main.js:407:25766)     at vTe.addTool (out/vs/workbench/workbench.desktop.main.js:944:2010)     at gRt.$registerToolWithDefinition (out/vs/workbench/workbench.desktop.main.js:945:45371)     at a._doInvokeHandler (out/vs/workbench/workbench.desktop.main.js:4930:51744)     at a._invokeHandler (out/vs/workbench/workbench.desktop.main.js:4930:51490)     at a._receiveRequest (out/vs/workbench/workbench.desktop.main.js:4930:50271)     at a._receiveOneMessage (out/vs/workbench/workbench.desktop.main.js:4930:49105)     at lIe.value (out/vs/workbench/workbench.desktop.main.js:4930:47177)     at E._deliver (out/vs/workbench/workbench.desktop.main.js:405:3150)     at E.fire (out/vs/workbench/workbench.desktop.main.js:405:3469)     at d3.fire (out/vs/workbench/workbench.desktop.main.js:996:9632)     at MessagePort.<anonymous> (out/vs/workbench/workbench.desktop.main.js:4945:16416)

Details

Property	Value
Bucket ID	0eead775-7688-8477-f5d4-39185d2389a4
Version	1.117.0
Commit	10c8e557
Last Seen	Sun Apr 26 2026 20:08:56 GMT+0000 (Coordinated Universal Time)
Platforms	Windows, Mac, Linux
Product	VSCode

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This issue was automatically created from the VS Code Errors Dashboard

[vs-code-engineering]

Stable Release Anomaly Details

• Anomaly type: spike — 10.3x increase
• Previous stable release: 1.116.0 — 7 users
• Current stable release: 1.117.0 — 72 users (89 hits)

Analysis

The deminified stack shows:

1. chatAgents.ts:540 → setRequestTools — throws "No activated agent with id 'setup.vscode'"
2. chatServiceImpl.ts:1240 — autorun reaction
3. observableInternal/reactions/autorunImpl.ts:110 → _run

This error fires during reactive updates when the setup.vscode agent is referenced but not yet activated (or has been deactivated). The throw site in chatAgents.ts:setRequestTools expects all referenced agent IDs to be activated. Related but distinct from older closed issues tracking setup.chat (#249632, #247517) — different agent ID and different call path.

Generated by errors-stable-scan · ● 9.6M · ◷

[vs-code-engineering]

🔍 Error Investigation

Summary

The setup.vscode agent is disposed when Copilot setup completes (context.state.completed becomes true), but an active chat request's autorun in chatServiceImpl.ts still holds a stale reference to the agent ID. When an extension registers a new tool (via RPC from the extension host), the observable tool set changes, the autorun fires, and setRequestTools throws because the agent no longer exists. This is a race condition between agent lifecycle and reactive tool updates. The 10.3× spike in 1.117.0 likely correlates with increased tool registrations from extensions during the setup→activated transition.

Culprit Commit

No specific culprit commit identified. This is a pre-existing race condition present since at least 1.111.0 (low-level occurrences across all versions). The autorun that calls setRequestTools was introduced in PR #301381 (1.112.0 milestone). The 10.3× spike in 1.117.0 is likely caused by an increase in the number of tools being registered by extensions during startup (widening the race window), not a single regression commit. No commit range was provided by the regression scan.

Code Flow

sequenceDiagram
    participant ExtHost as Extension Host
    participant MainThread as mainThreadLanguageModelTools
    participant ToolsService as languageModelToolsService
    participant Autorun as chatServiceImpl autorun
    participant AgentService as chatAgents.setRequestTools
    participant SetupContrib as chatSetupContributions

    Note over SetupContrib: setup.vscode registered<br/>(Copilot not yet activated)
    ExtHost->>MainThread: $registerToolWithDefinition
    MainThread->>ToolsService: addTool (line 174)
    Note over ToolsService: Observable set changes
    ToolsService->>Autorun: autorun fires (line 1258)
    Note over SetupContrib: ⚠️ context.state.completed = true<br/>vscodeAgentDisposables.clear()<br/>setup.vscode DISPOSED
    Autorun->>AgentService: setRequestTools("setup.vscode", ...)
    Note over AgentService: 💥 _agents.get("setup.vscode")<br/>returns undefined → throws

Loading

Affected Files

File	Role
src/vs/workbench/contrib/chat/common/participants/chatAgents.ts:537-543	Crash site — setRequestTools throws when agent not in _agents map
src/vs/workbench/contrib/chat/common/chatService/chatServiceImpl.ts:1258-1270	Root cause — autorun watches userSelectedTools but doesn't guard against disposed agent
src/vs/workbench/contrib/chat/browser/chatSetup/chatSetupContributions.ts:156-158	Trigger — vscodeAgentDisposables.clear() disposes setup agents on completion
src/vs/workbench/contrib/chat/common/tools/languageModelToolsService.ts:432	Data flow — addTool triggers observable change
src/vs/workbench/api/browser/mainThreadLanguageModelTools.ts:174	Entry point — extension tool registration via RPC

Repro Steps

1. Start VS Code with a fresh user data directory (Copilot not yet set up)
2. Open the Chat panel — setup.vscode agent is registered as placeholder
3. Send a chat message using the setup agent
4. While the request is in-flight, complete the Copilot setup flow (sign in, accept ToS)
5. An extension registers a new tool during activation — the autorun fires and throws

This is a race condition. The window is narrow but widens with more extensions registering tools during startup.

Fix Proposal

Fix location: src/vs/workbench/contrib/chat/common/participants/chatAgents.ts → setRequestTools()

Approach: Change setRequestTools to gracefully handle a missing/deactivated agent by returning early (like setYieldRequested already does at line 546-553), instead of throwing. The setRequestTools method is called from a reactive autorun that can outlive the agent's lifecycle — throwing here is inappropriate.

Note the inconsistency in the same file:

• setRequestTools (line 537): throws if agent missing ← bug
• setYieldRequested (line 546): silently returns if agent missing ← correct pattern
• getFollowups (line 555): returns [] if agent missing ← correct pattern

The fix is a one-line change: replace throw new Error(...) with return on line 540.

Alternatively, the autorun in chatServiceImpl.ts:1258-1270 could check if the agent is still registered before calling setRequestTools, but the defensive approach in chatAgents.ts is simpler and protects all callers.

Recommended Owner

@roblourens — author of PR #301381 which introduced the setRequestTools autorun, already assigned to this issue, and area owner for chat service infrastructure.

Generated by errors-investigate · ● 9.8M · ◷