fix(mcp): don't leave a server connected when tool discovery fails - #801
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serhiizghama wants to merge 2 commits into
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fix(mcp): don't leave a server connected when tool discovery fails#801serhiizghama wants to merge 2 commits into
serhiizghama wants to merge 2 commits into
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Register the client, transport, and config only after listTools() succeeds, and close the partially-established client on failure so its transport and child process don't leak.
serhiizghama
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August 6, 2026 01:48
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LGTM thanks @serhiizghama
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Closes #787.
connectToServer()registered the client, transport, and config in its internal maps right after the handshake but before callinglistTools(). So when a server connects fine but its initialtools/listfails, the rejection propagates as expected — but the server is left registered:isServerConnected()returns true,getServerInfo()reportsconnected: truewith zero tools, and the stdio child stays alive for the rest of the session.Moved the map registration to after
listTools()succeeds, so a server only becomes visible once both connection and tool discovery are done. The catch now also closes the partially-established client best-effort, so its transport / child process doesn't leak when discovery fails.Added two AVA tests around the connect lifecycle — one for the failed
listTools()path (rejects, nothing registered, client closed) and one confirming the success path still registers. They use a smallcreateClient()seam so the test can inject a client without standing up a real transport.