Summary

Auto Memory is documented as a Gemini CLI feature that "runs as a background task on session startup", but ACP session startup does not invoke the memory service.

As a result, users can enable experimental.autoMemory = true and use Gemini CLI through ACP/IDE flows, yet never get background extraction because the service is only started from the TUI/AppContainer path.

Repro

1. Enable Auto Memory in settings:

{
  "experimental": {
    "autoMemory": true
  }
}

2. Start Gemini CLI in ACP mode or via an ACP client / IDE integration.
3. Use the tool normally across multiple sessions.
4. Wait for the usual idle / eligibility conditions that Auto Memory expects.

Actual

ACP session creation succeeds, but Auto Memory startup is never invoked, so extraction never begins from that surface.

Expected

If experimental.autoMemory = true is supported generally, ACP sessions should also start the memory service on session boot.

If ACP is intentionally unsupported, the docs / settings surface should say so clearly, because the current documentation describes Auto Memory generically as a Gemini CLI session-start feature.

Verified Locally

I reproduced this by exercising GeminiAgent.newSession(...) with:

• a config mock where isAutoMemoryEnabled() returned true
• a spy on startMemoryService

The ACP session was created successfully and startMemoryService was never called.

Why This Matters

This surfaces for users who primarily work through IDE / ACP sessions:

• they enable Auto Memory in settings
• they expect background skill extraction to run on session startup
• inbox items never appear because extraction never starts on that client path

From the user perspective, the feature looks nonfunctional or inconsistent across Gemini CLI surfaces.

Relevant Code

• TUI startup path starts Auto Memory: packages/cli/src/ui/AppContainer.tsx:490
• ACP session startup does not: packages/cli/src/acp/acpClient.ts:266-356, packages/cli/src/acp/acpClient.ts:368-412
• Auto Memory docs describe generic session-start behavior: docs/cli/auto-memory.md:61