graph

The graph block chooses which graph implementation drives an agent block. It lives inside the agent block because the graph is part of the agent's definition, not a separate top-level build choice. In this distribution, the only shipped graph is react.

agent "assistant" {
  graph {
    type = "react"

    model {
      timeout = runtime("MODEL_TIMEOUT_MS", 30000)

      retry {
        max_attempts    = runtime("MODEL_MAX_ATTEMPTS", 3)
        initial_backoff = runtime("MODEL_INITIAL_BACKOFF_MS", 250)
        max_backoff     = runtime("MODEL_MAX_BACKOFF_MS", 5000)
      }
    }
  }
}

Fields

ReAct model call defaults

The optional model block sets startup defaults for calls made by the ReAct graph. Constant values are compiled into the generated configuration. A runtime() value creates an environment mapping that is resolved when the generated agent starts, so operators can tune the policy without compiling the agent again.

The timeout covers response stream establishment. It does not limit the total duration of a healthy streaming response. Retry applies only to transient failures that occur before the response stream is returned, including handshake timeouts and retryable provider failures. A stream that has already started is never restarted.

Clients may supply a model object when starting a ReAct run. Client timeout and retry values take precedence over these manifest defaults independently. For example, a request can replace the timeout while continuing to use the compiled retry policy. Provider, model, and inference parameter overrides remain request-only values and are not configured by this manifest block.

Usage

Graph selection is explicit. If a manifest omits the graph block, the compiler rejects it. That keeps the selected graph visible in the manifest and makes it possible for the compiler to compose the correct runtime pieces around it.

See The graph for the conceptual model, agent for the agent block that contains this block, and ReAct for the behavior and prompt variables of the shipped graph.