fix: Go 1.27 tooling — gofmt last + golangci v2.13.1 + errcheck v1.20.0

[bborbe]

Canonical Go 1.27.0 precommit fix (mirrors go-skeleton e7818706): errcheck v1.10.0 fails on Go 1.27 (package "flag" without types) — bumped to v1.20.0; golangci v2.13.1; gofmt last in format target. Precommit green.

[ben-s-pull-request-reviewer]

I now have all the information needed for the review.

Summary of findings:

• Mechanical finding: changelog/unreleased-entry-required (SHOULD) — CHANGELOG.md has no ## Unreleased bullet
• Judgment candidates: Makefile triggers node and go-makefile rules, but none are applicable (not a Node project, no test-as-verification issue, no build-args issue)
• The diff itself: version bumps in tools.env and gofmt ordering change in Makefile — both are legitimate tooling fixes

CANDIDATES: Rules matched by Step 4b-i — tools.env triggers no judgment rules; Makefile triggers node/make/* (Node.js, not applicable), go-makefile/test-not-build-for-verification (not triggered — this Makefile uses go test directly, not as a build proxy), and go-build-args/three-args-required (not triggered — no Dockerfile changes). Applicable set is empty.

Mechanical finding: changelog/unreleased-entry-required is applicable (CHANGELOG.md exists, non-vendored files changed, no Unreleased bullet).

---

{
"verdict": "request-changes",
"summary": "PR correctly bumps errcheck v1.20.0 and golangci-lint v2.13.1 for Go 1.27 compatibility and moves gofmt last in the format target. One SHOULD-fix remains: CHANGELOG.md has no ## Unreleased bullet for this source-changing PR, which would cause the autoRelease agent to no-op post-merge.",
"comments": [
{
"file": "CHANGELOG.md",
"line": 1,
"severity": "major",
"message": "changelog/unreleased-entry-required: PR changes source files but CHANGELOG.md has no '## Unreleased' bullet. In an autoRelease repo the release agent promotes '## Unreleased' post-merge; with none, no version ships. Add a conventional-prefixed bullet under '## Unreleased' (e.g. 'chore: Bump errcheck to v1.20.0 and golangci-lint to v2.13.1 for Go 1.27 support')."
}
],
"concerns_addressed": [
"correctness: errcheck v1.10.0 -> v1.20.0 — addressed by tools.env line 7",
"correctness: golangci-lint v2.12.2 -> v2.13.1 — addressed by tools.env line 10",
"correctness: gofmt moved to last in format target — addressed by Makefile lines 23-26"
]
}

---

Selector Mode Traceability

• Candidates: 0 judgment rules matched by Step 4b-i glob filter (Makefile triggers only node/make/* [not a Node project], go-makefile/test-not-build-for-verification [not applicable — test runs are not used as build proxy], go-build-args/three-args-required [not applicable — no Dockerfile/main.go changes], go-tools-versioning/no-tools-go-for-clis [script type, not judgment]; tools.env triggers no rules)
• Applicable: 0 rules selected by Step 4c-sel
• Skipped: N/A — all candidates correctly classified as non-applicable
• Mechanical findings: 1 (changelog/unreleased-entry-required, SHOULD tier — applied via Step 4a deterministic check)

---

Step 5: Consolidated Report

Must Fix (Critical)

None.

Should Fix (Important)

• CHANGELOG.md:1 — PR changes source files (Makefile, tools.env) but CHANGELOG.md has no ## Unreleased bullet. In an autoRelease repo the release agent promotes ## Unreleased post-merge; with none, no version ships. Add a conventional-prefixed bullet, e.g. chore: Bump errcheck to v1.20.0 and golangci-lint to v2.13.1 for Go 1.27 support. (rule: changelog/unreleased-entry-required)

Nice to Have (Optional)

None.

---

Step 6: Next Steps Recommendation

Add a ## Unreleased section to CHANGELOG.md with a chore: bullet covering both version bumps before merging.

Step 7: Manual Review

The version bumps (errcheck v1.10.0 → v1.20.0, golangci-lint v2.12.2 → v2.13.1) are correct for Go 1.27 compatibility. The gofmt reordering to run last in the format target is a standard pattern (run formatters first, gofmt as final pass). No source code behavioral changes. No cleanup needed (already at HEAD).

superseded by new automated review

[ben-s-pull-request-reviewer]

Analysis Complete

Now let me perform Step 4c-sel (CLASSIFY) — matching judgment rules against changed files:

Changed files:CHANGELOG.md, Makefile, tools.env

• changelog/conventional-prefix-required → skipped — CHANGELOG.md bullet uses chore: which IS a recognized prefix
• changelog/preamble-frozen → skipped — content added under ## Unreleased, not above the preamble
• changelog/unreleased-entry-required → skipped — ## Unreleased section now has a bullet
• go-licensing/source-file-header-required → skipped — no .go files changed
• go-licensing/license-file-required → skipped — LICENSE file exists
• go-makefile/test-not-build-for-verification → skipped — Makefile uses go test not go build for verification

No Go source files were changed, so no Go-specific rules apply.

Step 4d-sel (ADJUDICATE): The applicable set is empty → selector clean — no adjudication needed

---

Consolidated Report

Must Fix (Critical): None.

Should Fix (Important): None.

Nice to Have (Optional): None.

Selector mode traceability:

• Candidates: rules matching changed files (CHANGELOG.md, Makefile, tools.env)
• Applicable: 0 rules
• Skipped:changelog/conventional-prefix-required (prefix is valid chore:), changelog/preamble-frozen (content below preamble), changelog/unreleased-entry-required (bullet now exists), go-licensing/source-file-header-required (no Go files changed), go-licensing/license-file-required (LICENSE exists), go-makefile/test-not-build-for-verification (uses go test) — all non-applicable

Concerns from plan — reviewed:

• gofmt ordering in Makefile: gofmt now runs after goimports-reviser and golines — this is intentional; gofmt last ensures any reformatting from other formatters is normalized. No issue found.
• errcheck v1.10.0 → v1.20.0, golangci-lint v2.12.2 → v2.13.1: These are patch/minor bumps within the same tool series, compatible with Go 1.27. The CHANGELOG entry correctly describes the change. No issue found.

Notes:

• precommit skipped (selector mode) — CI covers lint+test
• Mechanical funnel: 0 findings (already computed)
• Step 4 skipped: no rule-relevant files changed (no .go files, no agent/command/skills/docs files, no secret/config files, no k8s files)

---

{
"verdict": "approve",
"summary": "Tooling update PR — errcheck and golangci-lint bumped for Go 1.27 compatibility, gofmt ordering corrected to run last in the format pipeline. CHANGELOG entry uses correct `chore:` prefix. No violations found.",
"comments": [],
"concerns_addressed": [
"correctness: gofmt ordering change in Makefile — verified gofmt now correctly runs after goimports-reviser and golines, no conflict",
"correctness: errcheck v1.20.0 and golangci-lint v2.13.1 versions verified compatible with Go 1.27 — not an issue"
]
}