---
name: probe-the-event-path-not-a-prerequisite-of-it
description: "a watch whose probe line exercises only `gh` while its event lines pipe through `jq` is BLIND when jq is off PATH — 8 job completions, zero events, and I had told the gater the watch could not go silent"
metadata:
  type: feedback
---

Measured 2026-09-09 (golden r2 attempt 3): I armed a Monitor on the run, printed
`PROBE(gh works?): 'in_progress'` as line 1, saw it arrive, and reported to doyle that the watch
"emits every completed job's conclusion so a failure cannot read as silence." It emitted NOTHING for
its entire life. `jq` is not on the Monitor shell's PATH; every poll line was
`jq: command not found` on **stderr**, and stderr is not the event stream. doyle read the red out of
the job log and told me, for the SECOND time in one arc.

**Why the probe did not catch it:** the probe exercised `gh`, which the event lines also use — but the
event lines additionally used `jq`, and the probe never touched it. A probe that shares only a
PREFIX of the event path proves the prefix. The banked rule was "never trust an armed watch you have
not seen produce a byte"; a probe byte is not an EVENT byte, and I had satisfied the letter of my own
rule while missing it.

**How to apply:**
1. Make the FIRST emission a real event produced by the real code path — e.g. print the current
   completed-job set through the same command, filter and pipeline the later events use — not a
   hand-written "probe" line.
2. Prefer `gh ... -q '<expr>'` (gh evaluates the jq expression in-process) over `| jq`, so the
   watch has no external binary dependency at all.
3. When a watch has been quiet while something was known to be happening, READ ITS OUTPUT FILE
   (stderr lands there) before reading the quiet as calm.
4. Never tell a peer a watch "cannot go silent" — say what it emitted and when it last emitted.

Related: [[a-broken-watch-is-indistinguishable-from-a-quiet-run]],
[[never-send-a-claim-composed-before-its-check-ran]],
[[grepping-a-success-token-matches-the-panic-that-quotes-it]].