hfdiff-sanity

name	hf.diff-sanity
description	Review branch diff for accidental deletions, debug code, missing imports, scope creep, and logic errors.

Diff Sanity Check

Review the current branch diff for common implementation mistakes before committing. This is a read-only check — it does not modify files.

When to Use

• After implementing changes, before committing
• As a pre-review sanity pass
• When you want a quick check for accidental mistakes

Instructions

1. Get the diff of changes on the current branch:

   git diff origin/main...HEAD
   

   If that's empty, fall back to git diff (unstaged) or git diff --cached (staged).

2. Review the diff for these problems:

   • Accidental deletions — unrelated code removed that should not have been
   • Leftover debug code — print(), console.log(), debugger, breakpoint(), commented-out code
   • Missing imports — new symbols referenced but not imported; removed code with stale imports
   • Scope creep — files changed that are unrelated to the issue
   • Hardcoded secrets or credentials — API keys, tokens, passwords in the diff
   • Broken string literals — unclosed quotes, malformed f-strings
   • Obvious logic errors — inverted conditions, off-by-one, unreachable code after return

3. For each problem found, note the file path, line, and description.

4. Produce structured output:

If all checks pass:

DIFF_SANITY_RESULT: OK
SUMMARY: No issues found

If problems are found:

DIFF_SANITY_RESULT: RETRY
SUMMARY: <comma-separated list of problem categories found>
FINDINGS:
- <file:line — description>

Important

• Do NOT modify any files. This is a read-only review.
• Focus on objective mistakes, not style preferences.
• If the diff is too large (>15,000 chars), summarize by file and focus on the riskiest changes.