# Todo 34: EventAgent History Boundary

## Status

done

## Goal

Ensure EventAgent receives only conversational `user` and `assistant` messages, not the full ChatAgent prompt/context list or EventAgent/tool internal replies.

## Plan

1. Add a runtime helper that derives EventAgent history from the current conversation.
2. Use it in both direct runtime and WebSocket session turn paths before enqueueing `EventAgentRequest`.
3. Add regression tests proving system prompts, pre-messages with system role, and internal EventAgent replies are excluded from EventAgent history and audit.

## Verification

- `uv run pytest tests/test_debug_runtime.py -q` passes (`21 passed`).
- `node --check src/agent_lab/presentation/static/app.js` passes.
- `uv run pytest` passes (`70 passed`, one existing Starlette deprecation warning).
- `git diff --check` passes.