Trait Tool

pub trait Tool: Clone {
    // Required methods
    fn name(&self) -> &'static str;
    fn description(&self) -> &'static str;
    fn input_schema(&self) -> Value;
    fn call(&self, arguments: &Value) -> Result<ToolResult, ToolError>;

    // Provided methods
    fn server_name(&self) -> String { ... }
    fn server_version(&self) -> &'static str { ... }
    fn capabilities(&self) -> Value { ... }
}

Trait that all FTL Core tools must implement

This trait defines a single computational tool optimized for WebAssembly performance. FTL Core follows the “1 tool per server” architecture for maximum efficiency.

Required Methods

fn name(&self) -> &'static str

The name of the tool (used in MCP tool calls)

fn description(&self) -> &'static str

Human-readable description of what the tool does

fn input_schema(&self) -> Value

JSON schema for the tool’s input parameters

Return a JSON object describing the expected input structure. Example:

{
  "type": "object",
  "properties": {
    "text": {
      "type": "string",
      "description": "The text to process"
    }
  },
  "required": ["text"]
}

fn call(&self, arguments: &Value) -> Result<ToolResult, ToolError>

Execute the tool with the provided arguments

This is where your tool’s core logic goes. The arguments are validated against your input schema before this method is called.

Provided Methods

fn server_name(&self) -> String

Optional: Custom server name (defaults to tool name)

fn server_version(&self) -> &'static str

Optional: Server version (defaults to “0.0.1”)

fn capabilities(&self) -> Value

Optional: Additional server capabilities

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors