radkit-macros

Procedural macros for the radkit agent framework.

Overview

This crate provides the #[skill] attribute macro for defining A2A-compliant agent skills with automatic metadata generation.

Usage

Add the macro to your skill struct and it will automatically generate the required SkillMetadata and implement the RegisteredSkill trait:

use radkit::prelude::*;
use radkit_macro::skill;

#[skill(
    id = "weather_checker",
    name = "Weather Checker",
    description = "Fetches weather information for any location",
    tags = ["weather", "api", "location"],
    examples = [
        "What's the weather in London?",
        "Check the forecast for Tokyo"
    ],
    input_modes = ["text/plain"],
    output_modes = ["application/json", "text/plain"]
)]
pub struct WeatherSkill;

#[async_trait]
impl SkillHandler for WeatherSkill {
    async fn on_request(
        &self,
        task_context: &mut TaskContext,
        context: &Context,
        runtime: &dyn Runtime,
        content: Content,
    ) -> Result<OnRequestResult, AgentError> {
        // Your skill implementation here
        Ok(OnRequestResult::Completed {
            message: Some(Content::from_text("Weather data retrieved")),
            artifacts: vec![],
        })
    }
}

Required Parameters

• id: A unique identifier for the skill (String)
• name: A human-readable name for the skill (String)
• description: A detailed description of what the skill does (String)

Optional Parameters

• tags: Array of keywords describing the skill's capabilities (default: [])
• examples: Array of example prompts or scenarios (default: [])
• input_modes: Array of supported input MIME types (default: [])
• output_modes: Array of supported output MIME types (default: [])

MIME Type Validation

The macro validates input_modes and output_modes against a list of common MIME types:

• Text types: text/plain, text/html, text/markdown, text/csv, etc.
• Application types: application/json, application/xml, application/yaml, application/pdf, etc.
• Image types: image/png, image/jpeg, image/svg+xml, etc.
• Wildcards: */*, text/*, application/*, image/*

If an invalid MIME type is provided, you'll get a compile error with suggestions for similar valid types.

What Gets Generated

The macro generates:

1. A static SkillMetadata constant named {STRUCT_NAME}_METADATA
2. An implementation of the RegisteredSkill trait for your struct

This allows you to register the skill with an agent builder:

let agent = AgentBuilder::new()
    .with_skill(WeatherSkill)
    .build(runtime)?;

Integration with A2A Protocol

The generated metadata is used to create the AgentSkill entries in your agent's AgentCard, making your skills discoverable and callable via the A2A protocol.

License

MIT