---
updatedAt: 2025-10-30T11:09:47.000Z
agentTools:
  projectIndex: https://api-docs.omnisend.com/v3/llms.txt
---

# Responses

## API Responses

Our APIs can return various types of responses to your requests. These responses follow the standard HTTP status codes and include both successful responses and error codes. You can find detailed explanations for these responses in the [Mozilla Developer Network HTTP Status documentation](https://developer.mozilla.org/en-US/docs/Web/HTTP/Status).

When interacting with our APIs, it's important to understand the meaning and implications of different response codes. Refer to the provided link to familiarize yourself with the various response types and ensure smooth integration with our services.

***

With **4xx** response (error) you'll receive in response body `error` with an error description and `fields` array with all errors.

```json
{
  "error": "Bad parameter: cartID not found.",
  "fields": {
    "0": [
      "'status' can't be 'unknown'. Available values: subscribed,nonsubscribed,nonSubscribed,unsubscribed"
    ]
  }
}
```