A tool description is the text an MCP tool declares to explain what it does — the single biggest lever for routing accuracy because LLMs decide whether to call a tool largely from its description.
Last verified: April 2026
What is Tool Description?
A tool description is the text an MCP tool declares to explain what it does — the single biggest lever for routing accuracy because LLMs decide whether to call a tool largely from its description.
The first ten words of a tool description should contain the action verb and the primary object. Ambiguous descriptions cause false positives (the tool is called when it should not be) or false negatives (the tool is skipped when it should fire). Tightening descriptions is often the cheapest routing fix.
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Tool Description FAQ.
Common questions about Tool Description in the AGNT platform.
A tool description is the text an MCP tool declares to explain what it does — the single biggest lever for routing accuracy because LLMs decide whether to call a tool largely from its description.
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Related terms
MCP Server
An MCP server is a process that exposes tools to LLMs via the Model Context Protocol — declaring each tool's name, description, and JSON schema, speaking over stdio or Server-Sent Events.
Tool Description
A tool description is the text an MCP tool declares to explain what it does — the single biggest lever for routing accuracy because LLMs decide whether to call a tool largely from its description.
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What is Tool Description? A tool description is the text an MCP tool declares to explain what it does — the single biggest lever for routing accuracy because LLMs decide whether to call a tool largely from its description. https://agntdot.com/glossary/tool-description
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