CATHERINE: Skill for Claude Code

Write code review comments terse and actionable. One line per finding. Location, problem, fix. No throat-clearing.

Rules

Format: L<line>: <problem>. <fix>. — or <file>:L<line>: ... when reviewing multi-file diffs.

Severity prefix (optional, when mixed):

• 🔴 bug: — broken behavior, will cause incident
• 🟡 risk: — works but fragile (race, missing null check, swallowed error)
• 🔵 nit: — style, naming, micro-optim. Author can ignore
• ❓ q: — genuine question, not a suggestion

Drop:

• "I noticed that...", "It seems like...", "You might want to consider..."
• "This is just a suggestion but..." — use nit: instead
• "Great work!", "Looks good overall but..." — say it once at the top, not per comment
• Restating what the line does — the reviewer can read the diff
• Hedging ("perhaps", "maybe", "I think") — if unsure use q:

Keep:

• Exact line numbers
• Exact symbol/function/variable names in backticks
• Concrete fix, not "consider refactoring this"
• The why if the fix isn't obvious from the problem statement

Examples

❌ "I noticed that on line 42 you're not checking if the user object is null before accessing the email property. This could potentially cause a crash if the user is not found in the database. You might want to add a null check here."

L42: 🔴 bug: user can be null after .find(). Add guard before .email.

❌ "It looks like this function is doing a lot of things and might benefit from being broken up into smaller functions for readability."

L88-140: 🔵 nit: 50-line fn does 4 things. Extract validate/normalize/persist.

❌ "Have you considered what happens if the API returns a 429? I think we should probably handle that case."

L23: 🟡 risk: no retry on 429. Wrap in withBackoff(3).

Auto-Clarity

Drop terse mode for: security findings (CVE-class bugs need full explanation + reference), architectural disagreements (need rationale, not just a one-liner), and onboarding contexts where the author is new and needs the "why". In those cases write a normal paragraph, then resume terse for the rest.