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

# JSONata Bindings Reference

> Bindings provide access to request and response data in mapping expressions

## Query Mapping Bindings

| Binding   | Description                       |
| --------- | --------------------------------- |
| `query`   | Query parameters from the request |
| `body`    | Request body                      |
| `context` | Account variables                 |
| `before`  | Results from before steps         |
| `id`      | Resource ID from URL              |

**Example:**

```jsonata theme={null}
{
  "warehouse_id": query.location_id,
  "limit": query.page_size
}
```

## Body Mapping Bindings

| Binding    | Description               |
| ---------- | ------------------------- |
| `body`     | Request body              |
| `query`    | Mapped query parameters   |
| `rawQuery` | Original query parameters |
| `context`  | Account variables         |
| `before`   | Results from before steps |

**Example:**

```jsonata theme={null}
{
  "order_name": body.name,
  "customer_email": body.customer.email
}
```

## Response Mapping Bindings

| Binding    | Description               |
| ---------- | ------------------------- |
| `response` | Raw API response          |
| `query`    | Mapped query parameters   |
| `rawQuery` | Original query parameters |
| `body`     | Request body              |
| `context`  | Account variables         |
| `headers`  | Response headers          |

**Example:**

```jsonata theme={null}
{
  "id": response.order_id,
  "status": $lowercase(response.order_status),
  "items": response.line_items.{
    "sku": sku,
    "quantity": qty
  }
}
```

## Header Mapping Bindings

| Binding   | Description             |
| --------- | ----------------------- |
| `headers` | HTTP headers            |
| `query`   | Mapped query parameters |
| `body`    | Request body            |
| `context` | Account variables       |

## Error Mapping Bindings

| Binding   | Description             |
| --------- | ----------------------- |
| `error`   | Error details           |
| `headers` | Response headers        |
| `body`    | Request body            |
| `query`   | Mapped query parameters |
| `context` | Account variables       |

## Before/After Step Bindings

| Binding   | Description             |
| --------- | ----------------------- |
| `id`      | Resource ID             |
| `query`   | Mapped query parameters |
| `body`    | Request body            |
| `context` | Account variables       |
| `step`    | Current step info       |

## Practical Example

**Query mapping:**

```jsonata theme={null}
{ "person_id": query.contact.id }
```

**Response mapping using the mapped value:**

```jsonata theme={null}
{
  "contact": {
    "id": query.person_id,
    "name": response.full_name
  }
}
```

## Common JSONata Functions

| Function       | Description          | Example              |
| -------------- | -------------------- | -------------------- |
| `$lowercase()` | Convert to lowercase | `$lowercase(status)` |
| `$uppercase()` | Convert to uppercase | `$uppercase(code)`   |
| `$now()`       | Current timestamp    | `$now()`             |
| `$count()`     | Count array items    | `$count(items)`      |
| `$sum()`       | Sum numbers          | `$sum(items.price)`  |
| `$merge()`     | Combine objects      | `$merge([a, b])`     |