fix(gateway): refresh cached agent tools on /reload-mcp#32815
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When the gateway processes /reload-mcp, it reconnects MCP servers and updates the global _servers registry, but cached AIAgent instances in _agent_cache keep the tools list they were built with. The user had to also run /new (discarding conversation history) before the agent could see the new tools — even though /reload-mcp had succeeded. This patch refreshes each cached agent's .tools and .valid_tool_names in _execute_mcp_reload after discovery returns, so existing sessions pick up new MCP tools on their next turn. The slash-confirm gate in _handle_reload_mcp_command already obtains user consent for the implied prompt-cache invalidation before this code runs. Mirrors the equivalent behaviour the CLI already does in cli.py _reload_mcp. Per-agent enabled_toolsets and disabled_toolsets are preserved so an agent that was scoped to a subset of toolsets does not silently gain disabled tools after the reload. Original diagnosis + initial implementation in #23812 from @fujinice. The auto-reload watcher half of that PR is intentionally dropped — users want /reload-mcp to remain explicit. Co-authored-by: fujinice <45688690+fujinice@users.noreply.github.com>
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🔎 Lint report:
|
| Rule | Count |
|---|---|
invalid-argument-type |
1 |
unresolved-import |
1 |
First entries
gateway/run.py:13363: [invalid-argument-type] invalid-argument-type: Argument to function `get_tool_definitions` is incorrect: Expected `list[str]`, found `Any | None`
tests/gateway/test_mcp_reload_refreshes_cached_agents.py:20: [unresolved-import] unresolved-import: Cannot resolve imported module `pytest`
✅ Fixed issues: none
Unchanged: 4967 pre-existing issues carried over.
Diagnostics are surfaced as warnings — this check never fails the build.
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Summary
/reload-mcpnow updates the running session's tool list — no/newrequired.Previously the gateway reconnected MCP servers but kept the stale tool list on every cached AIAgent. Users had to also start a new session to actually call the newly-available tools, losing their conversation history.
Changes
gateway/run.py::_execute_mcp_reload— afterdiscover_mcp_tools()returns, walk_agent_cacheand overwrite each agent's.tools+.valid_tool_namesviaget_tool_definitions(). Per-agentenabled_toolsets/disabled_toolsetsare preserved.tests/gateway/test_mcp_reload_refreshes_cached_agents.py— 3 new tests covering: cached agents are refreshed, empty cache is a no-op, and per-agent toolset scopes survive the reload.scripts/release.py— AUTHOR_MAP entry for @fujinice.What did NOT change
The slash-confirm gate (
Approve Once/Always Approve/Cancel) stays exactly as it was —/reload-mcpstill prompts before invalidating the prompt cache. The cache-refresh is just the missing piece of what "yes" already meant.The auto-reload-on-config-change watcher from #23812 is intentionally not included —
/reload-mcpremains explicit.Validation
/new)/reload-mcptests/gateway/(5923 tests)Credit
Original diagnosis + initial cache-refresh implementation by @fujinice in #23812 (Co-Authored-By preserved). Closes #23812.
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