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

# API Response

# Introduction

Our APIs respond with `data`, `errors`, and `metadata` blocks where appropriate. For example:

* `metadata` appears only for paginated responses,

* A response expected to return multiple entities may contain both `data` and `errors` blocks,

* `Entity IDs` are unique across all Retail Media entities.

## Response example

<CodeGroup>
  ```json JSON expandable theme={null}
  {
      "data": [
          {
              "type": "{entityType}",
              "id": "{entityId}",
              "attributes": {
                  "{fieldName}": {numericValue},
                  "{fieldName}": "{stringValue}",
                  // ...
              }
          },
          
          // ...
          
      ],
      "errors": [
          {
              "traceId": "{traceId}",
              "type": "{errorType}",
              "code": "{errorCode}",
              "instance": "{uri}",
              "title": "{errorTitle}",
              "detail": "{errorDetail}",
              "source": {
                  "{fieldName}": "{fieldPath}",
                  // ...
              }
          },
   
          // ...
           
      ],
      "metadata": {
          "totalItemsAcrossAllPages": {numberOfEntities},
          "currentPageSize": {pageSize},
          "currentPageIndex": {pageIndex},
          "totalPages": {numberOfPages},
          "nextPage": "https://api.criteo.com/{endpoint}?pageIndex={pageIndex}&pageSize={pageSize}",
          "previousPage": "https://api.criteo.com/{endpoint}?pageIndex={pageIndex}&pageSize={pageSize}"
      }
  }
  ```
</CodeGroup>

***

# Data Attributes

| Attribute    | Type   | Description                                                                                  |
| ------------ | ------ | -------------------------------------------------------------------------------------------- |
| `id`         | string | Unique ID for the entity. `Entity IDs` are unique across all Retail Media entities           |
| `type`       | string | Type of entity                                                                               |
| `attributes` | object | Entity attributes - may be omitted entirely if an entity does not have additional attributes |

***

# Error Attributes

| Attribute  | Type   | Description                                                         |
| ---------- | ------ | ------------------------------------------------------------------- |
| `traceId`  | string | Unique ID for the error response                                    |
| `type`     | string | Type of error; machine-readable (e.g. `validation`)                 |
| `code`     | string | Short machine-readable string for the error (e.g. `required-field`) |
| `instance` | string | URI referencing the endpoint that caused the error                  |
| `title`    | string | Short human-readable string that summarizes the issue               |
| `detail`   | string | Human-readable explanation of the issue                             |
| `source`   | object | Object referencing the field that caused the error                  |

***

# Pagination

* Pagination is supported via query parameters for a subset of endpoints that list multiple entities.

* Results are returned in ascending order by `id`

1. List all Accounts associated with your API credentials

2. List all Brands associated with the Account

3. List all Retailers associated with the Account

4. List all Campaigns within the Account

5. List all Line Items within the Campaign

6. List all Promoted Products on the Line Item

7. List all Balances on the Account

8. List all Campaigns on the Balance

| Query Parameters | Type    | Description                                                                                            |
| ---------------- | ------- | ------------------------------------------------------------------------------------------------------ |
| `pageIndex`      | integer | Returns the specified page of results given a `pageSize`; pages are 0-indexed                          |
| `pageSize`       | integer | Specifies the maximum number of entities returned in a single page; defaults to `25` entities per page |
| `limitToId`      | integer | Limits results to the entity IDs specified; parameter key is repeated, e.g. `limitToId=1&limitToId=2`  |

***

# HTTP Response Codes

| Response                  | Description                                                                                                             |
| ------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| 🔵`200 OK`                | Request successful                                                                                                      |
| 🔵`201 Created`           | The new entity was successfully created                                                                                 |
| 🔵`204 No Content`        | Request succeeded and no returned content should be expected                                                            |
| 🟡`207 Multi-Status`      | This may occur when operating on multiple entities, such as the call resulting in some successes but also some failures |
| 🔴`400 Bad Request`       | For improper syntax, check your call structure                                                                          |
| 🔴`401 Unauthorized`      | If unauthenticated, refresh your access token                                                                           |
| 🔴`403 Forbidden`         | Insufficient rights to perform this action                                                                              |
| 🔴`404 Not Found`         | Resource not found, check your entity IDs in the call                                                                   |
| 🔴`408 Timeout`           | Request timed out                                                                                                       |
| 🔴`409 Conflict`          | Request conflicts with something, such as a campaign name that already exists                                           |
| 🔴`429 Too Many Requests` | Too many requests                                                                                                       |
| 🔴`5xx`                   | Something's wrong on Criteo's end...                                                                                    |

***

**What’s Next**

* [API Pattern](/retail-media/v2024.10/docs/api-pattern)
* [Bulk Calls](/retail-media/v2024.10/docs/bulk-calls)
* [Campaign Structure](/retail-media/v2024.10/docs/campaign-structure)
* [List of Endpoints](/retail-media/v2024.10/docs/list-of-endpoints-including-preferred-deals)
* [Rate Limits](/retail-media/v2024.10/docs/rate-limits)
* [Statuses](/retail-media/v2024.10/docs/status)