a2a_agents/traits/
plugin.rs

1//! Core plugin trait for A2A agents.
2//!
3//! The `AgentPlugin` trait defines the interface that all agents should implement
4//! to integrate with the framework. It provides metadata, skill definitions, and
5//! lifecycle hooks.
6
7use a2a_rs::domain::A2AError;
8use a2a_rs::port::AsyncMessageHandler;
9use async_trait::async_trait;
10use serde::{Deserialize, Serialize};
11
12/// Skill definition for agent capabilities.
13///
14/// Skills describe what an agent can do, including keywords for intent matching,
15/// examples for documentation, and supported input/output formats.
16#[derive(Debug, Clone, Serialize, Deserialize)]
17pub struct SkillDefinition {
18    /// Unique identifier for the skill
19    pub id: String,
20    /// Human-readable name
21    pub name: String,
22    /// Description of what this skill does
23    pub description: String,
24    /// Keywords for intent classification
25    pub keywords: Vec<String>,
26    /// Example queries that trigger this skill
27    pub examples: Vec<String>,
28    /// Supported input formats (e.g., "text", "file", "data")
29    pub input_formats: Vec<String>,
30    /// Supported output formats (e.g., "text", "file", "data")
31    pub output_formats: Vec<String>,
32}
33
34/// Plugin trait that all agents should implement.
35///
36/// This trait extends `AsyncMessageHandler` with metadata and capability discovery.
37/// Agents implementing this trait can be automatically configured and discovered
38/// by the framework.
39///
40/// # Example
41///
42/// ```rust
43/// use a2a_agents::traits::{AgentPlugin, SkillDefinition};
44/// use a2a_rs::port::AsyncMessageHandler;
45/// use a2a_rs::domain::{A2AError, Message, Task};
46/// use async_trait::async_trait;
47///
48/// #[derive(Clone)]
49/// struct MyAgent;
50///
51/// impl AgentPlugin for MyAgent {
52///     fn name(&self) -> &str {
53///         "My Agent"
54///     }
55///
56///     fn description(&self) -> &str {
57///         "A simple example agent"
58///     }
59///
60///     fn skills(&self) -> Vec<SkillDefinition> {
61///         vec![
62///             SkillDefinition {
63///                 id: "hello".to_string(),
64///                 name: "Say Hello".to_string(),
65///                 description: "Greets the user".to_string(),
66///                 keywords: vec!["hello".into(), "hi".into()],
67///                 examples: vec!["Hello!".into()],
68///                 input_formats: vec!["text".into()],
69///                 output_formats: vec!["text".into()],
70///             }
71///         ]
72///     }
73/// }
74///
75/// #[async_trait]
76/// impl AsyncMessageHandler for MyAgent {
77///     async fn process_message(
78///         &self,
79///         task_id: &str,
80///         message: &Message,
81///         session_id: Option<&str>,
82///     ) -> Result<Task, A2AError> {
83///         // Implementation
84///         todo!()
85///     }
86///
87///     async fn validate_message(&self, message: &Message) -> Result<(), A2AError> {
88///         Ok(())
89///     }
90/// }
91/// ```
92#[async_trait]
93pub trait AgentPlugin: AsyncMessageHandler + Clone + Send + Sync + 'static {
94    /// Agent name (displayed to users)
95    fn name(&self) -> &str;
96
97    /// Agent description
98    fn description(&self) -> &str;
99
100    /// Version of the agent
101    fn version(&self) -> &str {
102        "1.0.0"
103    }
104
105    /// Skills provided by this agent
106    fn skills(&self) -> Vec<SkillDefinition>;
107
108    /// Optional: Initialize the agent (load models, connect to services, etc.)
109    async fn initialize(&mut self) -> Result<(), A2AError> {
110        Ok(())
111    }
112
113    /// Optional: Cleanup resources
114    async fn shutdown(&mut self) -> Result<(), A2AError> {
115        Ok(())
116    }
117
118    /// Optional: Health check
119    async fn health_check(&self) -> Result<(), A2AError> {
120        Ok(())
121    }
122}
a2a_agents/traits/plugin.rs

a2a_agents/traits/
plugin.rs
