Check reference / Triggering & Discoverability

MCPT-02 Tool descriptions anchor invocation

Triggering & Discoverability · 22% of the grade · live (--mcp-live) · applies to MCP configs

Live introspection — CLI-only, behind the explicit --mcp-live flag.

Why it matters

The model picks tools by their descriptions. A missing or title-length description means the tool loses to better-described alternatives — or gets called for the wrong jobs.

How to fix it

Give every tool a substantive description (a sentence or two): what it does, when to use it, and what it returns. Write it for the model choosing between twenty tools, not for a human reading docs.

Example

✗ flagged
"description": "Search"
✓ passes
"description": "Full-text search over the team's Confluence pages. Use when the user asks where something is documented. Returns the top 10 page titles with URLs."