fix: handle tools/resources/prompts list_changed notifications in client#2171
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giulio-leone wants to merge 1 commit intomodelcontextprotocol:mainfrom
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Previously, the client silently dropped ToolListChangedNotification, ResourceListChangedNotification, and PromptListChangedNotification from the server. They fell through to the catch-all case in _received_notification(). Add optional callbacks (tool_list_changed_callback, resource_list_changed_callback, prompt_list_changed_callback) following the same pattern as logging_callback. When set, the callbacks are invoked when the corresponding notification arrives. When not set, a no-op default is used (preserving backward compat). Updated both ClientSession and the high-level Client dataclass. Fixes modelcontextprotocol#2107 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Summary
Fixes #2107
The client silently drops
notifications/tools/list_changed,notifications/resources/list_changed, andnotifications/prompts/list_changednotifications from the server — they fall through tocase _: passin_received_notification().Root Cause
ClientSession._received_notification()only handledLoggingMessageNotificationandElicitCompleteNotification. The threelist_changednotification types (ToolListChangedNotification,ResourceListChangedNotification,PromptListChangedNotification) were caught by the catch-allcase _: passand discarded.Fix
Add optional callback parameters following the established
logging_callbackpattern:tool_list_changed_callback: ToolListChangedFnT | Noneresource_list_changed_callback: ResourceListChangedFnT | Noneprompt_list_changed_callback: PromptListChangedFnT | NoneEach callback is a simple
async def () -> Noneprotocol. When set, it is invoked upon receiving the corresponding notification. When not set, a no-op default is used (preserving backward compatibility).Both
ClientSessionand the high-levelClientdataclass are updated.Tests
5 new tests covering:
187/187 client tests pass (2 consecutive clean runs). ruff clean.