Check Impl Against Spec

This one checks your PR implementation against a spec file during code review. It reads spec_context.md, pulls out the concrete commitments (required behaviors, files to change, constraints), then compares them against the actual diff and flags material mismatches in review.json. The smart bit is it ignores harmless differences like naming tweaks and only complains about real problems: missing required behavior, contradictions to spec decisions, or absent migration steps. It folds findings into your existing review output rather than creating separate reports. Useful if your team writes specs before code and wants an automated sanity check that the PR actually delivers what was promised without getting pedantic about implementation details.

skills.sh installs: 27.1K
GitHub stars: 684
last updated: Aug 21, 2026

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Install

$ npx -y skills add warpdotdev/common-skills --skill check-impl-against-spec --agent claude-code

Installs into .claude/skills of the current project.

Files

Check implementation against spec

Use this skill only when spec_context.md exists during PR review.

Goal

Determine whether the implementation in the checked-out PR materially matches the approved spec context. This is a supplement to the normal code review, not a separate output.

Inputs

spec_context.md contains the spec context to compare against. It may include both product spec content (intended behavior, acceptance criteria) and tech spec content (implementation details, file changes).
pr_diff.txt contains the annotated diff for the PR.
pr_description.md may contain additional scope or rationale.
The working tree contains the PR branch contents.