Struct ToolDefinition 

pub struct ToolDefinition {
    pub name: String,
    pub description: String,
    pub input_schema: Value,
}

Tool definition for MCP tools/list response.

This struct represents a tool that can be called by MCP clients. It includes the tool’s name, description, and JSON Schema for input validation. This is a type-erased version that allows storing multiple tools with different input types in the same collection.

Fields

• name: Unique identifier for the tool
• description: Human-readable description of what the tool does
• input_schema: JSON Schema defining the expected input parameters

Example

use solidmcp::handler::ToolDefinition;
use serde_json::json;

let tool = ToolDefinition {
    name: "calculate".to_string(),
    description: "Perform arithmetic operations".to_string(),
    input_schema: json!({
        "type": "object",
        "properties": {
            "a": { "type": "number" },
            "b": { "type": "number" },
            "operation": {
                "type": "string",
                "enum": ["add", "subtract", "multiply", "divide"]
            }
        },
        "required": ["a", "b", "operation"]
    }),
};

Fields

name: String

description: String

input_schema: Value

Implementations

impl ToolDefinition

pub fn from_schema<T: JsonSchema>( name: impl Into<String>, description: impl Into<String>, ) -> Self

Create a new tool definition from a JsonSchema type.

This method automatically generates a JSON Schema from a Rust type that implements the JsonSchema trait. This is the preferred way to create tool definitions when using the framework API.

Type Parameters

• T: Type that implements schemars::JsonSchema

Parameters

• name: The unique name for this tool
• description: Human-readable description of the tool’s purpose

Returns

A new ToolDefinition with the schema automatically generated from type T

Example

use solidmcp::handler::ToolDefinition;
use schemars::JsonSchema;
use serde::Deserialize;

#[derive(JsonSchema, Deserialize)]
struct SearchInput {
    query: String,
    #[serde(default)]
    limit: u32,
}

let tool = ToolDefinition::from_schema::<SearchInput>(
    "search",
    "Search for items matching a query"
);

pub fn to_json(&self) -> Value

Convert to the JSON format expected by MCP protocol.

This method serializes the tool definition into the format required by the MCP protocol for the tools/list response.

Returns

A JSON value containing the tool’s name, description, and input schema

Example

let json = tool.to_json();
assert_eq!(json["name"], "calculate");
assert_eq!(json["description"], "Perform arithmetic operations");
assert!(json["input_schema"].is_object());

Trait Implementations

impl Clone for ToolDefinition

fn clone(&self) -> ToolDefinition

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ToolDefinition

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.