Session-Based Skill Maintenance

Purpose

Analyzes changes made in the current session to detect and fix verification skill drift:

1. •Missing coverage — Changed files not referenced by any verify skill
2. •Invalid references — Skills referencing deleted or moved files
3. •Missing checks — New patterns/rules not covered by existing checks
4. •Stale values — Configuration values or detection commands that no longer match

When to Run

• •After implementing a feature that introduces new patterns or rules
• •When modifying existing verify skills and wanting to check consistency
• •Before a PR to ensure verify skills cover changed areas
• •When a verification run missed expected issues
• •Periodically to align skills with codebase changes

Registered Verification Skills

List of verification skills registered in the current project. Update this list when creating/deleting skills.

Workflow

Step 1: Analyze Session Changes

Collect all files changed in the current session:

# Uncommitted changes
git diff HEAD --name-only

# Commits on the current branch (if branched from main)
git log --oneline main..HEAD 2>/dev/null

# All changes since branching from main
git diff main...HEAD --name-only 2>/dev/null

Merge into a deduplicated list. If an optional argument specifies a skill name or area, filter to relevant files only.

Display: Group files by top-level directory (first 1-2 path segments):

## Session Changes Detected

**N files changed in this session:**

| Directory | Files |
|-----------|-------|
| recommender/model | `svd.py`, `gmf.py` |
| recommender/libs | `name.py`, `module_path.py` |
| tests | `test_train.py` |
| (root) | `pyproject.toml` |

Step 2: Map Changed Files to Registered Skills

Reference the skills listed in the Registered Verification Skills section above to build a file-to-skill mapping.

Sub-step 2a: Check Registered Skills

Read each skill's name and covered file patterns from the Registered Verification Skills table.

If there are 0 registered skills, skip directly to Step 4 (CREATE vs UPDATE decision). All changed files are treated as "UNCOVERED".

If there is 1 or more registered skills, read each skill's .claude/skills/verify-<name>/SKILL.md and extract additional file path patterns from:

1. •Related Files section — Parse the table to extract file paths and glob patterns
2. •Workflow section — Extract file paths from grep/glob/read commands

Sub-step 2b: Match Changed Files to Skills

For each changed file collected in Step 1, compare against registered skill patterns. A file matches a skill if:

• •It matches the skill's covered file patterns
• •It is located within a directory referenced by the skill
• •It matches a regex/string pattern used in the skill's detection commands

Sub-step 2c: Display Mapping

### File → Skill Mapping

| Skill | Trigger Files (Changed Files) | Action |
|-------|-------------------------------|--------|
| verify-model-registration | `name.py`, `module_path.py` | CHECK |
| verify-test-coverage | `test_train.py` | CHECK |
| (no skill) | `pyproject.toml` | UNCOVERED |

Step 3: Coverage Gap Analysis for Affected Skills

For each AFFECTED skill (skills with matching changed files), read the full SKILL.md and check:

1. •Missing file references — Are changed files related to this skill's domain not listed in the Related Files section?
2. •Stale detection commands — Do the skill's grep/glob patterns still match the current file structure? Run sample commands to test.
3. •Uncovered new patterns — Read the changed files and identify new rules, configurations, or patterns that the skill doesn't check. Look for:
   • •New type definitions, enum variants, or exported symbols
   • •New registrations or configurations
   • •New file naming or directory conventions
4. •Residual references to deleted files — Are there files listed in the skill's Related Files that no longer exist in the codebase?
5. •Changed values — Have specific values (identifiers, config keys, type names) checked by the skill been modified in the changed files?

Record each gap found:

| Skill | Gap Type | Details |
|-------|----------|---------|
| verify-model-registration | Missing file | `recommender/model/new_model.py` not in Related Files |
| verify-test-coverage | New pattern | New model uses unchecked test patterns |

Step 4: CREATE vs UPDATE Decision

Apply the following decision tree:

For each uncovered file group:
    IF the file is related to an existing skill's domain:
        → Decision: UPDATE existing skill (expand coverage)
    ELSE IF 3+ related files share common rules/patterns:
        → Decision: CREATE new verify skill
    ELSE:
        → Mark as "exempt" (no skill needed)

Present results to the user:

### Proposed Actions

**Decision: UPDATE existing skill** (N)
- `verify-model-registration` — Add 2 missing file references, update detection patterns
- `verify-test-coverage` — Update detection commands for new patterns

**Decision: CREATE new skill** (M)
- New skill needed — Covers <pattern description> (X uncovered files)

**No action needed:**
- `pyproject.toml` — Config file, exempt
- `README.md` — Documentation, exempt

Use AskUserQuestion to confirm:

• •Which existing skills to update
• •Whether to create proposed new skills
• •Option to skip entirely

Step 5: Update Existing Skills

For each skill the user approved for update, read the current SKILL.md and apply targeted edits:

Rules:

• •Add/modify only — Never remove existing checks that still work
• •Add new file paths to the Related Files table
• •Add new detection commands for patterns found in changed files
• •Add new workflow steps or sub-steps for uncovered rules
• •Remove references to files confirmed deleted from the codebase
• •Update specific values (identifiers, config keys, type names) that have changed

Step 6: Create New Skills

Important: When creating a new skill, you must confirm the skill name with the user.

For each new skill to create:

1. •

   Explore — Read the related changed files to deeply understand the patterns

2. •

   Confirm skill name with the user — Use AskUserQuestion:

   Naming rules:

   • •The name must start with verify- (e.g., verify-auth, verify-api)
   • •Use kebab-case (e.g., verify-error-handling, not verify_error_handling)
3. •

   Create — Create .claude/skills/verify-<name>/SKILL.md following this template:

---
name: verify-<name>
description: <one-line description>. Use after <trigger condition>.
---

Required sections:

• •Purpose — 2-5 numbered verification categories
• •When to Run — 3-5 trigger conditions
• •Related Files — Table of actual file paths in the codebase (verified with ls, no placeholders)
• •Workflow — Check steps, each specifying:
  • •Tool to use (Grep, Glob, Read, Bash)
  • •Exact file paths or patterns
  • •PASS/FAIL criteria
  • •How to fix on failure
• •Output Format — Markdown table for results
• •Exceptions — At least 2-3 realistic "not a violation" cases

1. •

   Update related skill files — After creating a new skill, you must update these 3 files:

   4a. Update this file itself (manage-skills/SKILL.md):

   • •Add a new skill row to the table in the Registered Verification Skills section

   4b. Update verify-implementation/SKILL.md:

   • •Add a new skill row to the table in the Skills to Execute section

   4c. Update CLAUDE.md:

   • •Add a new skill row to the ## Skills table

Step 7: Verification

After all edits:

1. •Re-read all modified SKILL.md files
2. •Verify markdown formatting is correct (unclosed code blocks, consistent table columns)
3. •Verify no broken file references — For each path in Related Files, check file existence:

ls <file-path> 2>/dev/null || echo "MISSING: <file-path>"

1. •Dry-run one detection command from each updated skill to validate syntax
2. •Verify the Registered Verification Skills table and Skills to Execute table are in sync

Step 8: Summary Report

Display the final report:

## Session Skill Maintenance Report

### Files Analyzed: N

### Skills Updated: X
- `verify-<name>`: N new checks added, Related Files updated

### Skills Created: Y
- `verify-<name>`: Covers <pattern>

### Related Files Updated:
- `manage-skills/SKILL.md`: Registered Verification Skills table updated
- `verify-implementation/SKILL.md`: Skills to Execute table updated
- `CLAUDE.md`: Skills table updated

### Unaffected Skills: Z
- (No related changes)

### Uncovered Changes (no applicable skill):
- `path/to/file` — Exempt (reason)

Quality Criteria for Created/Updated Skills

All created or updated skills must have:

• •Actual file paths from the codebase (verified with ls), not placeholders
• •Working detection commands — Using real grep/glob patterns that match current files
• •PASS/FAIL criteria — Clear conditions for pass and fail for each check
• •At least 2-3 realistic exceptions — Descriptions of what is not a violation
• •Consistent formatting — Same as existing skills (frontmatter, section headers, table structure)

Related Files

Exceptions

The following are not issues:

1. •Lock files and generated files — uv.lock, poetry.lock, auto-generated migration files, and build outputs do not need skill coverage
2. •One-off config changes — Version bumps in pyproject.toml, minor linter/formatter config changes do not need new skills
3. •Documentation files — README.md, CHANGELOG.md, LICENSE, etc. are not code patterns requiring verification
4. •Test fixture files — Files in directories used as test fixtures are not production code
5. •Unaffected skills — Skills marked as UNAFFECTED do not need review
6. •CLAUDE.md itself — Changes to CLAUDE.md are documentation updates, not code patterns requiring verification
7. •CI/CD configuration — .github/, Dockerfile, etc. are infrastructure, not application patterns requiring verification skills