Free tool
Write a subagent that actually gets invoked
Fill in the form, get a working agent .md in the standard Claude Code layout. The preview updates as you type and nothing leaves this page. Save the file to .claude/agents/ in your repo, or ~/.claude/agents/ for every project.
What makes agents get invoked
- · description specificity beats prompt length — Claude picks agents by description, not by body
- · state when NOT to use it — it prevents wrong invocations as much as right ones
- · scope tools down — an agent that only reads should not be able to write
- · pin cheap models for mechanical work — haiku for formatting and extraction, opus only for judgment
code-reviewer.md
Also free: the skill validator — paste a SKILL.md and see why it is not triggering.
These tools check one file. The packs ship dozens that already pass.
See the packs