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Title: fix(mcp): retire pooled connections after consecutive request timeouts by waleedlatif1 · Pull Request #5821 · simstudioai/sim · GitHub

Open Graph Title: fix(mcp): retire pooled connections after consecutive request timeouts by waleedlatif1 · Pull Request #5821 · simstudioai/sim

X Title: fix(mcp): retire pooled connections after consecutive request timeouts by waleedlatif1 · Pull Request #5821 · simstudioai/sim

Description: Summary Follow-up to #5817, closing the P2 raised there ("Timed-Out Transport Remains Reusable"): a genuinely half-open transport could keep serving repeated 30s timeouts until the pool's liveness ping caught it. Adds a consecutive-timeout circuit breaker to the pool: a lone request timeout still keeps the session warm (retiring on every timeout is what caused the connect/stall/reconnect churn #5817 fixed), but two consecutive timeouts with no healthy request in between retire the connection. Any healthy release resets the count. withServerClient now reports sawTimeout on release; dead-connection errors still poison immediately, benign errors still keep the connection warm. Matches the LibreChat pattern (circuit breaker counts connection-level failures, not single request timeouts); the MCP SDK/OpenCode behavior for a lone timeout is unchanged. Type of Change Bug fix (resilience hardening) Testing 3 new pool tests: lone timeout keeps the connection; consecutive timeouts retire it (fresh connection on next acquire); healthy release resets the streak. Service test updated: timeout release reports (poison=false, sawTimeout=true). All 25 pool + service-pool tests green; tsc + biome clean. Checklist Code follows project style guidelines Self-reviewed my changes Tests added/updated and passing No new warnings introduced I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

Open Graph Description: Summary Follow-up to #5817, closing the P2 raised there ("Timed-Out Transport Remains Reusable"): a genuinely half-open transport could keep serving repeated 30s timeouts until the pool&...

X Description: Summary Follow-up to #5817, closing the P2 raised there ("Timed-Out Transport Remains Reusable"): a genuinely half-open transport could keep serving repeated 30s timeouts until t...

Opengraph URL: https://github.com/simstudioai/sim/pull/5821

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88c64c4 fix(mcp): retire pooled connections after consecutive request timeouts waleedlatif1 Jul 21, 2026 https://github.com/simstudioai/sim/pull/5821/commits/88c64c4b06c22173f881c3380a9c92b06125361e
67618a9 fix(mcp): classify TimeoutError-named aborts as timeouts for the circ… waleedlatif1 Jul 21, 2026 https://github.com/simstudioai/sim/pull/5821/commits/67618a99c77555507eade42c94ad7804370081e2
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