# Tutorial 3: Decisions

Branch workflow logic based on conditions — state values, payload answers, or complex expressions.

## Concepts Introduced

- `.WhenExpression()` — branch on any boolean expression
- `.WhenStateFlag()` — shorthand for checking a boolean state value
- `.WhenPayloadEquals()` — shorthand for checking a task completion payload value
- Nested decisions — decisions inside decisions for complex routing

## Decision Types

| Method | Use When |
|--------|----------|
| `WhenExpression` | Complex conditions (comparisons, boolean logic, function calls) |
| `WhenStateFlag` | Checking a boolean state key against true/false |
| `WhenPayloadEquals` | Checking a task completion answer (inside OnComplete) |

## Variants

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

## Next

[Tutorial 4: Human Tasks](../04-human-tasks/) — approve/reject patterns with OnComplete flows.