Agentic Development · Architecture
A structured definition (usually JSON Schema) that describes a tool's name, what it does, and what parameters it accepts. The model reads this to know how and when to call the tool.
Example: { name: 'search_web', description: 'Search the internet for current info', parameters: { query: { type: 'string' } } }
In practice: Well-written tool descriptions are crucial. The model decides whether to use a tool based almost entirely on the description. Vague descriptions lead to misuse or tools being ignored.