Attribute Macro tool 

#[tool]

The #[tool] procedural macro.

Transforms a function into a full Tool implementation.

Attributes

• #[tool(description = "...")] — Required. The tool description shown to the LLM.
• #[param(desc = "...")] — Optional per-parameter. Adds description to the JSON schema.

Parameter Rules

• String, i64, f64, bool → required in schema
• Option<T> → optional in schema
• Vec<T> → array in schema