Review Pattern Skill

Analyze pattern documentation against real implementations to find gaps that would cause confusion or errors during implementation.

Prerequisites

Run this skill from a consuming repo (one that uses the patterns), not from effect-patterns itself. The skill needs real code to compare against.

Workflow

1. •

   Map argument to pattern file

   • •repository → repository-pattern.md
   • •http-api or http → http-api-pattern.md
   • •error or error-handling → error-handling-pattern.md
   • •schema → schema-pattern.md
   • •testing or test → testing-pattern.md
   • •form → form-pattern.md
   • •effect-atom or atom → effect-atom-pattern.md
   • •service → service-pattern.md
   • •policy → http-api-pattern.md (policies section)
2. •

   Read the pattern file from the patterns location (check CLAUDE.md for path)

3. •

   Find 2-3 real implementations in the current codebase

   • •Use Glob/Grep to find code following this pattern
   • •Pick varied examples (simple + complex cases)
4. •

   Perform gap analysis using the criteria in GAP-ANALYSIS.md

5. •

   Generate improvement report (see output format below)

Evaluation Dimensions

Focus on these four dimensions (details in GAP-ANALYSIS.md):

Output Format

# Gap Analysis: [pattern-name]

## Summary

- **Pattern length**: X lines (target: <800)
- **Real implementations examined**: [list files]
- **Critical gaps**: X found
- **Minor gaps**: X found

## Critical Gaps

Issues that would cause implementation errors or require significant correction.

### 1. [Gap title]

**Found in**: `path/to/real/implementation.ts:42`
**Pattern says**: [what the doc says or omits]
**Code actually does**: [what real code does]
**Suggested fix**: [specific text to add/change in pattern]

### 2. ...

## Minor Gaps

Issues that would require lookup or cause minor friction.

### 1. [Gap title]
...

## Redundancy Check

Sections that could be trimmed without losing information:
- [section name]: [why it's redundant]

## Suggested Edits

Concrete changes to make, in priority order:

1. **[Location in pattern]**: [exact change]
2. ...

What Makes a Critical Gap

A gap is critical if any of these apply:

• •Missing import would cause compile error
• •Wrong file path would put code in wrong location
• •Omitted step would cause runtime error
• •Ambiguous instruction has multiple valid interpretations

A gap is minor if:

• •Information exists but is hard to find
• •Example works but isn't idiomatic
• •Related pattern link is missing

Length Guidelines

Count only the rendered content, not template syntax.