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filip131311
7f85f996aa
## Summary Fixes **bucket B** of the 0.16.0 crash telemetry — the `toolserver_bind` / `EADDRINUSE` restart loop. It's the largest crash **volume** (~817 events, one machine alone = 785) even though it's a narrow user set (10). Companion to #531 (which fixed the widespread multi-user bucket A). ## Root cause (reproduced live) The main HTTP listener's `server.on("error")` handler routed **every** bind error through `crashShutdown` (exit 1). When a second tool-server starts on an already-owned port, that exit just feeds a supervisor respawn → re-bind → crash, forever. The telemetry signature was puzzling: all these crashes are `crash_phase=serving` with ~1s uptime and **0 tool calls** — i.e. the listener *bound successfully* and then died. I reproduced it: on macOS, a **second tool-server process's** `listen()` momentarily **succeeds** (the `listening` callback runs → `listening=true` → phase `serving`), and **then** the server emits an asynchronous `EADDRINUSE`. So the redundant instance binds, immediately errors, crashes, and the supervisor loops it (~1s each, 785× on one machine). Live A/B on the compiled `dist` (isolated port, telemetry disabled), server A up then a second server B on the same port: ``` buggy (current 0.16.0): B: "Tools server listening ..." → "Failed to bind ... EADDRINUSE" → exit 1 (→ respawn loop) fixed: B: "Tools server listening ..." → "deferring to it (redundant instance)" → exit 0 ``` A survives in both. ## Fix Handle `EADDRINUSE` specifically instead of crash-looping: - Probe the port for a healthy argent tool-server (`GET /tools` → 200, or 401 when a token is configured). - **If a healthy peer answers**, this instance is redundant → shut down **cleanly** (`shutdown(0)`) and defer to it. This removes it from the `reason:"crash"` restart-loop population entirely. - **If nothing healthy owns the port** (a foreign holder, or a wedged peer that doesn't answer within the probe timeout) → still crash, so a genuinely stuck port stays visible. - `EACCES` and all other server errors crash exactly as before. It also corrects the now-false comment claiming these crashes are phased `startup` ("the listen callback never ran"). Telemetry and the live repro prove the bind succeeds first, so `listening=true` and the phase is genuinely `serving`. ## Testing - **New unit tests** for `probeArgentToolServer`: peer answering 200 or 401 → `true`; foreign 500, connection-refused, and wedged/timeout → `false`. - Full tool-server suite **2731 green**; `tsc` + `eslint` clean. - **Live A/B** above, on the built dist. ## Note on scope This is a robustness fix that breaks the loop for the redundant-instance case (the dominant one). The precise reason macOS lets a second process's bind succeed-then-error asynchronously (vs. failing immediately, as same-process contention does) is a kernel/loopback timing detail; the fix does not depend on it — any `EADDRINUSE`, immediate or deferred, now defers-or-crashes deterministically rather than hot-looping.