werkrevisor/docs/prs/2026-10-17-PR#120-codex-timer-1min.md

PR#120: The Codex Runner Starts 1 Minute after Its Last Run

Version: patch

WARNING: This document describes only the change applied in this PR. It may already be outdated once the next PR is merged. Historic PR documentation is not maintained along with new PRs; treat it as a snapshot.

Related Links

• PR#88: the Codex runner and its systemd units.

Problem

The timer starts the Codex runner 5 minutes after the end of its last run (OnUnitInactiveSec=5min). Over the 49 Codex reviews since 2026-10-10, the time from the werkrevisor result to the Codex result has a median of 3.4 minutes and a p90 of 6.5 minutes; most of it is the gap of the timer. A run without a ready PR takes about 5 s and 2 s CPU.

Non-Goals

• No parallel reviews: they would save about 1 minute in rare cases, and attempts.json and the fetches of the mirrors would need locks.
• No change of the installed unit on the workstation; the human installs it after the merge.

Solution

• tools/systemd/werkrevisor-codex-runner.timer: OnUnitInactiveSec=1min.
• config/codex-runner.toml: max_reviews_per_run = 1.
• The docstring of tools/codex-runner, the README and the config name the new interval and the new purpose of max_reviews_per_run.
• Version 0.47.1.

Open Questions

• Does max_reviews_per_run = 3 still fit a run each minute? No; it is now 1. The quota of the subscription is weekly, so the bound per run does not change the total use. The bound now limits how old the view of a run gets: the runner reviews the heads it saw at its start, and a review takes several minutes, so the third review of a run could review a head that a push already replaced. With 1 review per run, the next run starts 1 minute later and sees the current heads. A backlog of several ready PRs costs 1 minute more per PR; only 4 of 45 runs had a second ready PR.