Retries and timeouts

Agent model resilience belongs in AgentConfig.Middlewares. Import pkg/agents/middleware for retries and fallback around a complete model call, including stream consumption.

Retry before trying another model

With a model client configured for every target provider:

config.Middlewares = []agents.Middleware{
    middleware.NewFallbackModels("Anthropic/your-fallback-model"),
    middleware.NewRetry(middleware.RetryConfig{MaxAttempts: 3}),
}

The first middleware is outermost. This ordering gives each target its retry budget before moving to the next model. MaxAttempts includes the initial call. Configure Backoff, Retryable, or RetryableStreamError to customize classification and delay. Retries and fallback stop once a chunk has been published, so two attempts cannot be mixed into one visible answer. Cancellation, deadlines, stream-transform failures, and stop requests also prevent repetition. The durable adapters recognize terminal model-call failures so activity retries do not restart an exhausted policy.

Agent and provider middleware

pkg/gateway/middleware wraps direct provider operations and is configured through hastekit.WithMiddleware. pkg/agents/middleware wraps the agent’s model operation and is configured through AgentConfig.Middlewares. Avoid stacking retry policies at both layers unintentionally; their attempt budgets can multiply. See provider configuration for direct model requests and provider keys.

Bound execution time

For a caller-bound run:

runCtx, cancel := context.WithTimeout(ctx, 2*time.Minute)
defer cancel()
result, err := agent.Run(runCtx, &hastekit.Input{
    Message: hastekit.UserTurn("Summarize the report."),
})
if err != nil { return err }
_ = result

Run cancellation cancels local work and signals remote execution through the broker. Execute starts detached execution: cancelling its context disconnects observation, and cancelling handle.Wait stops only that wait. Use handle.Stop to request execution cancellation. MaxLoops bounds the model loop, not elapsed time or spending. Frontend tools have a separate wait timeout, and external APIs should have their own deadlines. Tools must honor context cancellation; a timeout cannot roll back a completed external action.

Getting started

Core concepts

Models and providers

Tools and capabilities

Multi-agent patterns

Interfaces

Durable execution

Scheduled work

Workflows

Testing and operations

Retries and timeouts

Retry before trying another model

Agent and provider middleware

Bound execution time

​Retry before trying another model

​Agent and provider middleware

​Bound execution time

Retry before trying another model

Agent and provider middleware

Bound execution time