---
title: 'Overview'
description: 'The hybrid: a durable workflow owns the fixed, auditable steps and hands the open-ended judgment to an in-process deep agent.'
position: 1
---

# Workflow agents

> A workflow agent is the hybrid of the two building blocks. A durable
> [workflow](/docs/sdk/workflows/overview) owns the fixed, auditable part of a
> process, and it hands the open-ended judgment to a conversational
> [agent](/docs/sdk/agents/overview) from inside a step. The run stays durable and
> auditable while the agent handles the part you cannot write down in advance.

A workflow is durable and deterministic but cannot hold a free-form
conversation. An agent reasons through fuzzy input but has no durable pipeline,
retries, or audit trail.

## Two directions

- A workflow delegates to an agent, which is the common case. A step runs one turn
  of a sibling agent, in-process, and reads back its reply. Because it runs
  in a `'use step'`, the reply is a durable checkpoint.

  ```ts
  import { callDeepAgent } from '@stackbone/sdk/workflow';

  async function askAgent(message: string) {
    'use step';
    const { text } = await callDeepAgent('support', message);
    return text;
  }
  ```

  Use `streamDeepAgent` instead of `callDeepAgent` when you want the reply
  streamed live into the run's chat surface. It runs the same in-process turn
  and returns the same durable `{ text }`, but the Studio Playground serves the
  workflow as a token-by-token chat rather than a one-shot run. The
  `stackbone add workflow-agent` scaffold generates this streaming call.

- An agent starts a workflow. A tool's handler can launch a long-running
  workflow with `stackbone.workflows.start(name, input)` (fire-and-forget) or
  `startAndWait(...)` when it needs the result before replying.

## When to use it

Pick the hybrid when a process has a rigid outline and a judgment-heavy middle:
triage then act, or draft then approve. If it is a pure conversation, use a plain
[agent](/docs/sdk/agents/overview). If it is a fixed pipeline, use a plain
[workflow](/docs/sdk/workflows/overview).

Scaffold the whole thing in one command:

```sh
stackbone add workflow-agent lead-qualifier
```

## Where to go next

- **[Getting started](/docs/sdk/workflow-agents/getting-started)**: scaffold and
  run a hybrid end to end.
- **[Examples](/docs/examples/workflow-agents/delegate-to-agent)**: a delegating workflow, an
  agent that starts a workflow, and a draft-then-approve flow.
- **[Agents](/docs/sdk/agents/overview)** and
  **[Workflows](/docs/sdk/workflows/overview)** are the two building blocks on
  their own.