Workflows as agent tools

workflow.NewTool wraps a Go-built or YAML-compiled graph as an agents.Tool. The model selects when to run it and supplies its arguments; the graph defines the steps inside that call.

Create the wrapper

With compiled ready:

tool, err := workflow.NewTool("review_payment", "Review a proposed payment.",
    map[string]any{
        "type": "object",
        "properties": map[string]any{"amount": map[string]any{"type": "number"}},
        "required": []string{"amount"},
        "additionalProperties": false,
    }, compiled)
if err != nil { return err }
_ = tool

Add tool to AgentConfig.Tools. The wrapper validates the JSON input schema and arguments. Tool arguments become RunContext.input; application run context becomes RunContext.context. Namespace, thread, and session metadata come from the calling agent, not model-provided arguments.

Interruptions and results

A workflow pause becomes an agent interruption. The wrapper serializes the checkpoint into ToolCallResponse.StateUpdates, keyed by the tool and outer call ID. Resume using the agent’s normal resolution messages; there is no second workflow-specific tool the model needs to call. A completed result contains workflow context excluding the application context field. Avoid copying credentials or private context into ordinary node output, which can be returned to the model.

Runtime boundaries

The wrapper accepts ordinary workflow.InvokeOption values. Its default is the in-process workflow runtime. Merely giving the parent agent a Temporal runtime does not turn each inner workflow node into its own Temporal activity: the tool executes inside the parent’s tool boundary. The explicit Temporal graph executor is registered separately and uses Temporal workflow context. Connecting it through a custom agent tool requires an application bridge that starts or calls the registered Temporal workflow. Persist the parent agent’s history and keep the graph stable for paused calls. Side effects before a saved checkpoint can repeat if the enclosing tool activity retries. Use idempotency at those boundaries.

Getting started

Core concepts

Models and providers

Tools and capabilities

Multi-agent patterns

Interfaces

Durable execution

Scheduled work

Workflows

Testing and operations

Workflows as agent tools

Create the wrapper

Interruptions and results

Runtime boundaries

​Create the wrapper

​Interruptions and results

​Runtime boundaries

Create the wrapper

Interruptions and results

Runtime boundaries