Runtime

The core of Radkit’s architecture is the Runtime trait. It acts as a centralized service hub or dependency injection container for your agent. Instead of passing many different service handles (like a database connector, a logger, etc.) to every function, your SkillHandlers receive a single, unified reference: &dyn Runtime.

This design keeps your agent logic clean, decoupled from infrastructure, and highly portable.

The Runtime Trait

All runtime environments, whether for local development or cloud deployment, must implement the Runtime trait. This guarantees a consistent interface for your skills.

pub trait Runtime {
    fn task_manager(&self) -> Arc<dyn TaskManager>;
    fn memory_service(&self) -> Arc<dyn MemoryService>;
    fn logging_service(&self) -> Arc<dyn LoggingService>;
    // ... other services
}

Your skill code is written against this abstraction, not a concrete implementation. A skill simply asks the runtime for a service:

// Inside a SkillHandler method...
let memory_service = runtime.memory_service();
memory_service.save(auth_ctx, "some_key", &data).await?;

The skill doesn’t know or care if memory_service is writing to an in-memory map for local testing or a massive, persistent cloud database.

Core Services

The Runtime provides access to a set of essential services, each defined by its own trait.

• TaskManager: A Data Access Object (DAO) for persisting and retrieving the state of A2A Tasks and their event histories. This is crucial for multi-turn conversations and auditing.
• MemoryService: Provides a persistent, tenant-aware key-value store. This is ideal for giving your agent long-term memory or for implementing Retrieval-Augmented Generation (RAG).
• LoggingService: A structured logging interface that streams logs to the console during local development or to a cloud observability UI in production.
• AuthService: Identifies the current user and tenant, ensuring that all other services are properly namespaced and data is kept secure.

Provided Runtimes

Radkit provides a DefaultRuntime for local development, and the architecture allows for custom runtimes for production or specialized environments.

DefaultRuntime

Included with the runtime feature flag, DefaultRuntime is an out-of-the-box implementation that works on both native and WASM targets. It provides simple, in-memory versions of all the core services, allowing you to get up and running instantly with no configuration.