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

# Naming conventions

> PascalCase entities, snake_case variables and fields, and topic naming basics for maintainable LoT systems.

## Why naming matters

Consistent naming is the single most impactful practice for maintainable LoT systems. These conventions apply to all LoT entities and keep notebooks readable as your project grows.

<Tip>
  **Like street names in a city.** Predictable patterns let anyone find an address without a map — and let AI assistants generate code that matches your project.
</Tip>

***

## Entity names

All LoT entities use **PascalCase**. Names should be descriptive and purpose-driven.

| Entity           | Convention                    | Good Examples                                                    | Bad Examples                          |
| ---------------- | ----------------------------- | ---------------------------------------------------------------- | ------------------------------------- |
| Actions          | PascalCase, verb-first        | `ProcessTemperature`, `MonitorPressure`, `SendDailyReport`       | `temp_process`, `action1`, `myAction` |
| Models           | PascalCase, noun-based        | `SensorReading`, `EquipmentStatus`, `ProductionRecord`           | `sensor_model`, `Model1`, `data`      |
| Rules            | PascalCase, descriptive scope | `AllowAdminActions`, `ProtectSysTopics`, `RestrictDevicePublish` | `Rule1`, `myRule`, `newRule`          |
| Routes           | PascalCase, destination-based | `CloudBridge`, `SensorDatabase`, `AlertEmail`                    | `route1`, `my_route`, `dbRoute`       |
| Callable Actions | PascalCase, function-like     | `CalculateAverage`, `ConvertCelsiusToFahrenheit`                 | `calc`, `helper`, `util`              |

***

## Variable names

Variables use **snake\_case** inside double quotes for `SET` declarations, and **curly braces** for references.

```lot wrap theme={"theme":"css-variables","languages":{"custom":["/languages/lot.json"]}}
DEFINE ACTION ProcessSensorData
ON TOPIC "sensors/+/raw" DO
    SET "sensor_id" WITH TOPIC POSITION 2
    SET "raw_value" WITH (GET JSON "value" IN PAYLOAD AS DOUBLE)
    SET "converted_value" WITH ({raw_value} * 1.8 + 32)
    PUBLISH TOPIC "processed/" + {sensor_id} + "/fahrenheit" WITH {converted_value}
```

| Context             | Convention                    | Examples                                             |
| ------------------- | ----------------------------- | ---------------------------------------------------- |
| Declaration (`SET`) | `snake_case` in double quotes | `"sensor_id"`, `"raw_value"`, `"cycle_time"`         |
| Reference           | Curly braces                  | `{sensor_id}`, `{raw_value}`, `{cycle_time}`         |
| Model fields        | `snake_case` in double quotes | `"equipment_id"`, `"runtime_hours"`, `"last_update"` |
| Action inputs       | `snake_case` after keyword    | `INPUT value AS DOUBLE`, `INPUT threshold AS DOUBLE` |

***

## Topic names

Topics use **lowercase with forward-slash separators**. Multi-word segments use **snake\_case**.

Whenever possible, follow a **Unified Namespace (UNS)** format for topic naming. This enables readability and scalability as systems grow.

| Pattern                     | Example                                                           | Use Case               |
| --------------------------- | ----------------------------------------------------------------- | ---------------------- |
| `domain/entity/attribute`   | `sensors/temperature/value`                                       | General data           |
| `domain/instance/attribute` | `sensors/temp001/raw`                                             | Instance-specific data |
| `domain/category/instance`  | `alerts/critical/pump03`                                          | Categorized events     |
| Prefixed namespaces         | `processed/`, `alerts/`, `config/`, `cache/`, `state/`, `system/` | Functional separation  |

For hierarchy design, functional namespaces, and domain-specific UNS patterns, see [Designing your data layer](./data-layer).

***

## Next Steps

<CardGroup cols={2}>
  <Card title="Designing your data layer" icon="sitemap" href="/v2.0/lot-language/usage-patterns/data-layer">
    Topic trees, payload formats, and model inheritance.
  </Card>

  <Card title="Anti-patterns" icon="triangle-exclamation" href="/v2.0/lot-language/usage-patterns/anti-patterns">
    Common mistakes and what to do instead.
  </Card>
</CardGroup>