# Tutorial 4: Human Tasks with OnComplete Flows

The approve/reject pattern — the most common human task flow in insurance workflows.

## Concepts Introduced

- `WorkflowHumanTask.For<T>()` — define a task with name, type, route, and roles
- `.WithPayload()` — data sent to the UI when the task is displayed
- `.WithTimeout(seconds)` — optional deadline for the task
- `.WithRoles()` — restrict which roles can interact with this task
- `.OnComplete(flow => ...)` — sequence executed after user completes the task
- `.ActivateTask()` — pause workflow and wait for user action
- `.AddTask()` — register a task in the workflow spec (separate from activation)
- Re-activation — send the user back to the same task on validation failure

## Approve/Reject Pattern

1. Workflow starts, runs some service tasks
2. `.ActivateTask("Approve")` — workflow pauses
3. User sees the task in their inbox, assigns it, submits an answer
4. `.OnComplete` checks `payload.answer`:
   - `"approve"` — run confirmation operations, convert to policy
   - `"reject"` — cancel the application
5. If operations fail, re-activate the same task for correction

## Variants

- [C# Fluent DSL](csharp/)
- [Canonical JSON](json/)

## Next

[Tutorial 5: Sub-Workflows](../05-sub-workflows/) — inline vs fire-and-forget child workflows.