[Danathar]

Problem

When a PR has more changed files than GitHub's files API returns (3000), ListPRChangedFiles returns an error wrapping ErrIncompletePRFileList. The contributor lane (evaluateContributorLanePR) handed that error back like a transport fault. The PR never gets fewer files, so the sweep logged WARN contributor-lane automerge sweep skipped PR … reason=contributor-lane:files-evidence error=incomplete PR file list on every tick. On reef that was 117 times in 10 minutes for one PR (5204 files), and the fleet reporter filed it as unclassified_error_repeated.

Fix

Treat ErrIncompletePRFileList as a standing files-evidence verdict with a nil error. adoptionDiffRefusal already does this for the same condition.

• The PR still fails closed. Its diff fences can't be read, so the lane never merges it.
• The sweep now logs the ordinary automerge skip info line instead of the WARN.
• The merge-request relay returns a files-evidence refusal instead of a "lane evidence unavailable" error.
• Real transport failures, such as a 5xx on the files API, still return the error and the WARN.

Tests

• TestTrySweepContributorLanePRSkipReasons/incomplete_files_list: changed_files=5204 → reason files-evidence, nil error, no merge.
• TestRelayMergeRefusalFailsClosed/incomplete_files_list_refuses: the relay returns a refusal, not an error.
• Added a changelog fragment.

Fixes #18121

🤖 Generated with Claude Code

— hive: backend=claude model=claude-opus-5-5

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🐝 Hive Agent: contributor | SHA: eb4d4743f

[kubestellar-prow]

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[hivecommons-hive]

Docs-currency review at head 9627e88: no blocking doc drift.

Advisory (non-blocking):

• changelog.d/fixed-18121-contributor-lane-incomplete-files.md:1 omits the issue link. changelog.d/README.md (Format → Content) asks for "issue links" in the entry. Optional suggestion:

- The contributor-lane automerge sweep now treats a PR with more changed files than GitHub's files API returns (3000) as a standing `files-evidence` skip instead of re-warning every sweep (#18121).

• Out-of-scope, pre-existing: src/docs/labels-and-control-signals/stage-labels.md:1018-1019 says a file list shorter than changed_files "waits for the next sweep". The doc comment on adoptionDiffRefusal (automerge_contributor_adopt.go) calls that case a standing verdict. This PR does not touch that path.

— hive: agent=adjudicator-5 backend=claude model=claude-sonnet-5-5 claude=2.1.322

[hivecommons-hive]

Review follow-ups (below review.backlog.min_severity: P2)

Non-blocking findings below the backlog filing line are listed here instead of as issues, one comment per PR, updated in place. Tick them off as they are fixed; set review.backlog.min_severity: P3 to file every finding.

• P3 low docs-currency — stage-labels.md calls incomplete file list a per-sweep deferral (src/docs/labels-and-control-signals/stage-labels.md:1018): src/docs/labels-and-control-signals/stage-labels.md:1018 says a short file list waits for the next sweep, but adoptionDiffRefusal treats it as a standing verdict with a nil error. Pre-existing; this …

[hivecommons-hive]

Hive status — updated in place; edits do not notify. Full history is in the Activity Monitor.

Evidence bundle `#181249627e88` sha256:58e57ac545eaf311b9f4affdc243f44a05e7c054e2bda7584cd092192a61d30e — download from the dashboard or `hivectl review evidence #18124`.

[hivecommons-hive]

merged by Hive trusted-author auto-merge: author @Danathar holds role owner and GitHub permission maintain on repo; CI green at 9627e88.