PR 27827 runtime verification
main: 955e2bfbb5c092c54ad795c8d379fec99702a6b5
head: 581aeeb8697a35e6753dd3776c6014f642dd3962
Chrome / Playwright; fresh isolated state; real git repository added through UI; Codex gpt-6.1-sol.
Scenario: obtain real draft thread id from the sender; open that route in a second client without draft storage. Hold delivery of its real server 404 until the sender creates the thread and begins a real Codex turn. No synthetic response body or provider output.
main 04:56:16.269 UTC: bounded snapshot 404. Sender completed tool call and SNAPSHOT-RECOVERY-OK. Observer remained empty, with no snapshot retry.
PR 04:59:25.056 UTC: bounded snapshot 404.
PR 04:59:29.034 UTC: bounded snapshot retry 200. Observer showed user prompt, real sleep tool call, and SNAPSHOT-RECOVERY-OK without reload.
Neighbor checks: ordinary new-thread reply; follow-up SNAPSHOT-FOLLOWUP-OK; offline/online reconnect; full reload restored both messages. Delete via thread menu + confirmation removed separate baseline thread and navigated away; zero bounded snapshot retries in 10 seconds.
Blacksmith: 47/47 threads-sync tests passed. check:changed against PR base 8f79233ccb0509f44ac54cb13d011676c9a6451c: format, lint, knip, typecheck (7 packages), focused tests all passed.
Not exercised: native desktop/mobile, relay/tunnel remote environment, other providers. Race required controlled delivery timing of the real 404; ordinary current-main composer flow already avoids early detail loading.