The merged detector's 0.6 flag threshold had become the close bar, and 6 of the 7 real flagged pairs at 85% or more were not duplicates. The sweep now closes only when an older open issue has the identical normalized title, measures the grace period from the latest bot notice, and leaves the issue open when anyone replies or gives the notice a thumbs down.
A reporter cannot reopen an issue the bot closed, so a reporter comment after the automatic close reopens it, drops the duplicate label, and asks for a human look. Manual dispatch defaults to a dry run and takes a grace_period_days input, the runner supplies the repository, the dead python closer is gone, and the decision core has bun tests on a PR-triggered job.
The setup step ran `bun-version: latest`, carried over from the upstream layout,
and the step after it holds an issues: write token. A compromised Bun release
would have executed privileged in that job and could rewrite or close issues.
Pinned to 1.4.0, the release the passing runs already resolved to. setup-bun
takes no checksum input, so pinning the action by sha and the runtime by exact
version is as far as this can be hardened without hand-rolling the download.
Moves the sweep out of inline workflow JavaScript and into scripts/, following
the layout anthropics/claude-code uses for the same job: a checked-out repo, a
sha-pinned setup-bun step, and `bun run scripts/auto-close-duplicates.ts`.
The script mirrors that repo's file shape, keeping the same request helper,
interfaces, per-issue debug logging, and top-level catch, so the two read the
same way side by side.
Two things stay deliberately different. Candidates come from the notice marker's
digits-only field rather than a regex over the comment prose, because titles are
attacker-controlled and are interpolated into that same comment. The label is
also added on its own endpoint instead of alongside the state change, since
sending labels with a PATCH replaces every label already on the issue.
