Skillcheck

Skills Check

Validate skill quality across one or more skill directories.

Preprocessing Lint

Scan SKILL.md files for <bang>`command` patterns that trigger Claude Code's preprocessor unintentionally:

!bun ${CLAUDE_PLUGIN_ROOT}/skills/skillcheck/scripts/lint-preprocessing.ts ${ARGUMENTS:-${CLAUDE_PLUGIN_ROOT}}

Interpreting Results

The linter reports:

• File path and line number of each finding
• The matched pattern and surrounding context
• Summary counts (clean, skipped, issues)

Fixing Issues

The <bang> Convention

SKILL.md files are preprocessed by Claude Code — any <bang>`command` syntax executes when the skill loads. To safely document or reference the syntax:

• In SKILL.md: use <bang> as a stand-in for !
• In reference files (references/, EXAMPLES.md): literal ! is fine and encouraged
• In command files (commands/*.md): literal ! is required (that's the feature)

Skills that intentionally preprocess (running scripts at load time) should declare it:

metadata:
  preprocess: true

Additional Checks

Beyond preprocessing, verify skill quality with existing tools:

# Frontmatter validation
bun ${CLAUDE_PLUGIN_ROOT}/scripts/validate-skill-frontmatter.ts <path-to-SKILL.md>

# Full plugin validation
bun ${CLAUDE_PLUGIN_ROOT}/scripts/validate-plugin.ts <plugin-directory>

Deep Validation

After reviewing linter results, spawn the quartermaster agent to run deeper validation — frontmatter schema, naming conventions, description quality, line counts, and reference integrity. Pass it the same path argument.

Quality Checklist

• No unintentional <bang>`command` in SKILL.md (this linter)
• Valid frontmatter (name, description, required fields)
• SKILL.md under 500 lines
• All referenced files exist
• Description has WHAT + WHEN + trigger keywords