fix(stdio): handle EPIPE errors gracefully in StdioServerTransport#1566
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opspawn wants to merge 2 commits intomodelcontextprotocol:mainfrom
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fix(stdio): handle EPIPE errors gracefully in StdioServerTransport#1566opspawn wants to merge 2 commits intomodelcontextprotocol:mainfrom
opspawn wants to merge 2 commits intomodelcontextprotocol:mainfrom
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…client disconnect When an MCP client disconnects abruptly before the server finishes writing its response, stdout.write() throws an unhandled EPIPE error that crashes the entire server process. This commit adds proper error handling for the stdout stream in StdioServerTransport: - Register an 'error' event listener on stdout during start(), matching the existing pattern for stdin error handling - Clean up the stdout error listener in close() - Reject the send() promise when a write error occurs during backpressure (when waiting for 'drain') This ensures EPIPE and other stdout write errors are routed through the transport's onerror callback instead of becoming unhandled exceptions. Fixes modelcontextprotocol#1564 Signed-off-by: opspawn <sean@opspawn.com> Signed-off-by: OpSpawn <opspawn@users.noreply.github.com>
🦋 Changeset detectedLatest commit: e1913ee The changes in this PR will be included in the next version bump. This PR includes changesets to release 4 packages
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@modelcontextprotocol/client
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Signed-off-by: Sean <sean@opspawn.com>
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Summary
Fixes #1564 —
StdioServerTransportcrashes with unhandled EPIPE when the client disconnects while the server is writing to stdout.Changes
stdouterror event listener instart()to catch EPIPE/write errorsclose()to prevent leakssend()when backpressure drain fails due to a closed pipeTest plan
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