fix(everything): stop long-running operation when the request is cancelled - #4847
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Ewertonslv wants to merge 1 commit into
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…elled trigger-long-running-operation waited on plain setTimeout promises and never looked at extra.signal, so after a client cancelled the request the loop kept running and sending progress notifications. On stdio this held the process open and delayed shutdown. Wait with node:timers/promises setTimeout and pass the request signal, so the pending timer is cleared and the handler rejects as soon as the request is aborted. Fixes modelcontextprotocol#4846
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Description
trigger-long-running-operationwaited on plainsetTimeoutpromises and never checkedextra.signal. When a client cancelled the request, the loop kept running to the end and kept sending progress notifications. On stdio the pending timers held the process open, which is what delays shutdown in #4846.The wait now uses
setTimeoutfromnode:timers/promiseswith the request's abort signal. When the request is cancelled, the pending timer is cleared and the handler rejects immediately, so no further steps or progress notifications run.Fixes #4846
Server Details
trigger-long-running-operation)Motivation and Context
The Everything server is the reference for how MCP features should behave. A long-running tool that ignores cancellation shows the wrong pattern, and it keeps stdio clients from shutting down cleanly after a cancel.
How Has This Been Tested?
Added
should stop when the request is cancelledtosrc/everything/__tests__/tools.test.ts. It starts the operation with anAbortControllersignal, aborts after 50 ms, and asserts that the handler settles within 500 ms without sending any progress notification.expected 'still running' to be 'stopped'.npx vitest run __tests__/tools.test.ts: 62 passed.npx tsc --noEmit: clean.I did not test it against an LLM client.
Breaking Changes
None. Calls that are not cancelled behave the same as before.
Types of changes
Checklist