Registered tools are the specific capabilities (like "Book a Table" or "Add to Cart") that your website exposes to AI agents.
How the Registered WebMCP tools audit works
This audit is informational. Lighthouse lists all WebMCP tools registered on the page using the Declarative or Imperative APIs. If no tools are registered, the result list will be empty.
How to fix
You can register tools using either the Declarative API or the Imperative API:
- Declarative API: Add
toolnameandtooldescriptionattributes directly to your<form>elements. - Imperative API: Use JavaScript to register tools using
navigator.modelContext.registerTool.
Best practices
- Use clear, action-oriented names (for example,
toolname="book_appointment"). - Provide detailed descriptions that explain what the tool does and when an agent should use it.
- If you want to learn more, read the WebMCP documentation.