A pre-PR checklist cut one contributor's unmerged PRs from 62% to 14%, and does not predict anyone else's

The repository is a question list, packaged as a skill for Claude Code and Codex, to run before a pull request opens. The author's own numbers on the smol machines organization's repositories: the share of closed PRs that went unmerged fell from 62% in August to 14% in October, and the share of changed lines that never merged fell from 47% to 3%. Merged output stayed near 0.7 to 0.85 PRs a day, so the questions stopped wasted work rather than speeding up merged work. The author states the limits: one person, no control group, and growing familiarity with the project.

The evaluation directory also reports three studies on other projects (Godot, ollama, excalidraw, helix, nest, SvelteKit, Vue). Scoring outside contributors' PRs against the questions did not separate merged from rejected ones; none of the studies met the bar the author set (Fisher p < 0.05 and a 20-point gap). The directory includes the scores and an analyze.py script that, per the README, reproduces the study numbers. This run read the README and results tables but did not run the script.

Why it matters: The author's own conclusion is that the questions work as a check on your own change, not as a filter for other people's. Teams scoring agent-written PRs against a checklist before review should treat that result as a warning: a checklist that did not predict merges across 783 outside PRs is a weak gate.