> ## Documentation Index
> Fetch the complete documentation index at: https://docs.worlds.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Choosing Your Workflow Pattern

> A decision guide for selecting the right trigger mode, signal type, and check nodes for your use case

Every Worlds workflow starts with the same fundamental decisions. This guide walks you through those decisions to help you pick the right configuration.

## Decision 1: What are you monitoring?

The first question determines your **signal type**.

| You care about...                                                                                 | Signal Type         | Example                                     |
| ------------------------------------------------------------------------------------------------- | ------------------- | ------------------------------------------- |
| **A specific object's behavior** — where it goes, how long it stays, how fast it moves            | Track State         | Obstruction, wrong-way, speeding, loitering |
| **What's happening in a zone** — how many objects are in it, regardless of which specific objects | Zone State          | Congestion, congregation, occupancy limits  |
| **How two objects interact** — proximity, overlap, co-location                                    | Track State (batch) | Near-miss, PPE compliance, tailgating       |

## Decision 2: Do you need real-time alerting?

This determines your **mode**.

<Tabs>
  <Tab title="Yes — use Streaming">
    You need to react while conditions are developing. The workflow executes on every detection update.

    **Trade-offs:**

    * Higher processing volume (hundreds of executions per track)
    * Can alert while the event is still happening
    * Required for zone state monitoring
    * Must handle event closure separately (close path on the orchestrator)

    **Available signal types:** Track State, Zone State
  </Tab>

  <Tab title="No — use Batch">
    You only need to know after the fact. The workflow executes once per track after it expires.

    **Trade-offs:**

    * Much lower processing volume (one execution per track)
    * Delayed by the batch interval (10–300 seconds)
    * Complete track lifecycle available — can set event start and end time at creation
    * Interaction data available for Type III checks
    * Track State only (zone state is not available in batch)

    **Available signal types:** Track State only
  </Tab>
</Tabs>

## Decision 3: Which check node?

Based on your signal type, choose the appropriate check node(s):

### For Track State

| Check Type                                                          | Use when...                                                                                                 | Requires           |
| ------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------- | ------------------ |
| [**Type I**](/nodes/type-1-track-in-zone) — Track in Zone           | You need to check if a track is in a zone meeting threshold conditions (dwell time, intersection, velocity) | Streaming or Batch |
| [**Type II**](/nodes/type-2-zone-sequence) — Zone Sequence          | You need to check if a track visited zones in a specific order                                              | Streaming or Batch |
| [**Type III**](/nodes/type-3-track-interaction) — Track Interaction | You need to check if two tracks interacted (proximity, overlap)                                             | **Batch only**     |

These can be [composed together](/concepts/check-chaining) — chain multiple check types and the Event Orchestrator evaluates them with AND or OR logic.

### For Zone State

| Check Type                                            | Use when...                                                                                                 |
| ----------------------------------------------------- | ----------------------------------------------------------------------------------------------------------- |
| [**Zone Activity Check**](/nodes/zone-activity-check) | You need to check aggregate zone conditions (track count, per-track dwell time and intersection thresholds) |

## Decision 4: Event scope

The [Event Orchestrator](/nodes/event-orchestrator) prevents duplicate events by scoping them to an entity:

| Scope      | Use when...                  | Example                                                              |
| ---------- | ---------------------------- | -------------------------------------------------------------------- |
| **Track**  | One event per tracked object | Obstruction — each vehicle gets its own event                        |
| **Zone**   | One event per zone           | Congestion — one event per zone regardless of which tracks are in it |
| **Device** | One event per camera         | Camera-level alerting                                                |
| **Site**   | One event per site           | Site-wide incident tracking                                          |

## Quick reference: common use cases

| Use Case                | Mode      | Signal Type | Check         | Scope | Guide                                  |
| ----------------------- | --------- | ----------- | ------------- | ----- | -------------------------------------- |
| Obstruction / loitering | Batch     | Track State | Type I        | Track | [Guide](/guides/batch-track-state)     |
| Congestion              | Streaming | Zone State  | Zone Activity | Zone  | [Guide](/guides/streaming-zone-state)  |
| Zone intrusion          | Streaming | Track State | Type I        | Track | [Guide](/guides/streaming-track-state) |
| Wrong-way detection     | Streaming | Track State | Type II       | Track | —                                      |
| Speeding in zone        | Streaming | Track State | Type I        | Track | —                                      |
| Safety near-miss        | Batch     | Track State | Type III      | Track | —                                      |
| PPE compliance          | Batch     | Track State | Type III      | Track | —                                      |
| Congregation            | Streaming | Zone State  | Zone Activity | Zone  | —                                      |
| Checkpoint bypass       | Streaming | Track State | Type I + II   | Track | —                                      |

## Workflow template

Every workflow follows the same core structure:

```
Trigger → Check(s) → Event Orchestrator → Action(s)
```

### Minimal workflow

```
Trigger → Check → Orchestrator → Event Manager (create)
```

### Standard workflow

```
Trigger → Check → Orchestrator ─┬─ Create: Image → Event Manager → (GIF → Email)
                                └─ Close: Event Manager (close)
```

### Advanced workflow (with VLM)

```
Trigger → Check → Orchestrator ─┬─ Create: Closest Frame → Image → VLM → Merge → Metadata → Event Manager
                                └─ Close: Event Manager (close)
```

Start with the minimal pattern and add complexity only as your use case requires.