Assembly follows conventional HTTP response codes to indicate the success or failure of an API request and uses the following codes:

| Error Code | Meaning |
| --- | --- |
| 200 | OK — Everything worked as expected. |
| 400 | Bad Request — The request was unacceptable, typically due to an invalid or missing parameter. |
| 401 | Unauthorized — No valid API key provided. |
| 404 | Not Found — The requested resource doesn't exist. |
| 429 | Too Many Requests — Too many requests hit the API too quickly. |
| 500 | Internal Server Error — There was an error with Assembly's servers. Try again later or contact Assembly support. |

## Error Response

Some errors that could be handled programmatically (e.g., a parameter is invalid) include an error response object that explains the error reported.

**code**`string`

Specialized identifier for this type of error in our API. Mostly returned with `4xx` errors and briefly explains the error reported.

**message**`string`

Human readable error message describing the issue.

**data**`string or object`

Additional information provided about an error for `5xx` response status.