While studying the simple chatbot's context-management lifecycle, I found Server._cleanup_lock confusing because the example does not appear to invoke cleanup concurrently on the same Server.
Source: examples/clients/simple-chatbot/mcp_simple_chatbot/main.py.
The current call paths are sequential:
Server.initialize() awaits self.cleanup() on initialization failure before re-raising.ChatSession.start() awaits cleanup_servers() in its initialization-error handler and again in its finally block.cleanup_servers() awaits each server's cleanup in reverse server order.
Repeated cleanup calls therefore do not overlap in the demonstrated flow. A single AsyncExitStack.aclose() already awaits the registered exits sequentially in reverse order, so the lock is not needed to make session teardown precede transport teardown.
Suggested simplification: remove the _cleanup_lock initialization and the async with self._cleanup_lock: wrapper, retaining the existing cleanup body and error handling. Alternatively, a brief comment explaining an intended concurrent-caller use case would clarify why the lock is retained.
This is an example-code clarity/simplification request based on source inspection, not an observed runtime bug or a claim that locks are unnecessary for concurrent cleanup generally. Removing it would remove serialization for callers that use this class concurrently outside the demonstrated flow; that tradeoff needs maintainer judgment. No runtime tests were performed for this report.
Reporting first per the contribution guide. AI assistance: prepared with OpenAI Codex after discussing the example and inspecting its cleanup call paths.
While studying the simple chatbot's context-management lifecycle, I found
Server._cleanup_lockconfusing because the example does not appear to invoke cleanup concurrently on the sameServer.Source:
examples/clients/simple-chatbot/mcp_simple_chatbot/main.py.The current call paths are sequential:
Server.initialize()awaitsself.cleanup()on initialization failure before re-raising.ChatSession.start()awaitscleanup_servers()in its initialization-error handler and again in itsfinallyblock.cleanup_servers()awaits each server's cleanup in reverse server order.Repeated cleanup calls therefore do not overlap in the demonstrated flow. A single
AsyncExitStack.aclose()already awaits the registered exits sequentially in reverse order, so the lock is not needed to make session teardown precede transport teardown.Suggested simplification: remove the
_cleanup_lockinitialization and theasync with self._cleanup_lock:wrapper, retaining the existing cleanup body and error handling. Alternatively, a brief comment explaining an intended concurrent-caller use case would clarify why the lock is retained.This is an example-code clarity/simplification request based on source inspection, not an observed runtime bug or a claim that locks are unnecessary for concurrent cleanup generally. Removing it would remove serialization for callers that use this class concurrently outside the demonstrated flow; that tradeoff needs maintainer judgment. No runtime tests were performed for this report.
Reporting first per the contribution guide. AI assistance: prepared with OpenAI Codex after discussing the example and inspecting its cleanup call paths.