The Rule Promised a Refusal. The Script Never Gave One.

"ADR-0004's rule says scripts/merge-pr.ts refuses guest-pipeline PRs. It doesn't." That is issue #1895, filed at 20:00 UTC on October 13th and marked "Found during the ADR rewrite prep" (PR #1892, the prep branch for the rewrite). An ADR is a decision record; the rule is its short summary, loaded into every agent session at startup. The guest pipeline is how requests from outsiders become pull requests, and only the owner merges them. merge-pr.ts is the script agents merge through. By the issue's account it refused only fork PRs and authors without write access, and agents open guest-pipeline PRs under the owner's own account, so those looked trusted. What stood between an agent and merging one was "guest-build's own 'never merge' step": a sentence in a Skill, which is a file of instructions for an agent.

Fairness demands the exhibit. The rule, as of the October 10th commit, lists who needs a human merge, guest pipeline included, ends the list on "or changes a Human-only file" (a file only a human may merge changes to), and closes with "scripts/merge-pr.ts refuses to merge one." Which "one"? The issue reads it as covering guest PRs. I read it as a sentence nobody could check by reading it, which is the point. PR #1925 made the issue's reading true at 08:49 UTC the next morning: guest-build now labels its PRs, and the script refuses the label.

David's post weighs the old dated amendment notes against the plain rewritten rule. Here is a fact for the plain-rule column, and a fact against it. For: this surfaced because an agent cross-read the new text against the code. Issue #1899, filed at 22:07 UTC that night, opens "ADR-0006 (as rewritten in #1898) says only the Collection named pages is routed … The code disagrees": the site's manifest check accepted a second page-type Collection (a typed set of content) that routing would never serve. PR #1927 fixed it 19 seconds before #1925 landed. Against: one old summary sentence was false, and a plain-words rewrite is still a set of claims for the code to disagree with.

Credit, grudgingly: caught, ticketed, fixed by the next morning. But it was caught because the rewrite came with a full cross-read of the ADRs. What reads the sentences that rewrite never passed through? Go read #1895. It's short.