Step Types

Step type enum is defined in src/types.zig; validation rules are in src/workflow_validation.zig; execution behavior is in src/engine.zig.

Supported Types

• task
• fan_out
• map
• reduce
• condition
• approval
• transform
• wait
• router
• loop
• sub_workflow
• debate
• group_chat
• saga

Validation Rules On `POST /runs`

• step ids must be unique and non-empty
• depends_on must be an array of known step ids
• duplicate dependency entries are rejected
• retry.max_attempts and timeout_ms must be positive integers

Type-specific requirements:

• loop: requires body
• sub_workflow: requires workflow
• wait: requires one of duration_ms, until_ms, signal
• router: requires routes
• saga: requires body
• debate: requires count
• group_chat: requires participants

Example: Minimal DAG

{
  "steps": [
    {
      "id": "research",
      "type": "task",
      "worker_tags": ["researcher"],
      "prompt_template": "Research {{input.topic}}"
    },
    {
      "id": "write",
      "type": "task",
      "depends_on": ["research"],
      "worker_tags": ["writer"],
      "prompt_template": "Write summary: {{steps.research.output}}"
    }
  ],
  "input": { "topic": "DAG engines" }
}