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

# UNSUPPORTED_VERSION

> Unsupported API version (400)

`Pulse-Version` names a version this API doesn't serve; `supported` lists the ones it does.

| Status | Retryable | Title |
| - | - | - |
| `400` | No | Unsupported API version |

## What to do

Send one of the versions `supported` lists, or leave the header out to use your organization's.

## Example

```json theme={null}
{
  "type": "https://docs.runpulse.com/errors/unsupported-version",
  "title": "Unsupported API version",
  "status": 400,
  "detail": "Unsupported Pulse-Version: '3'",
  "instance": "urn:pulse:request:req-6f1c2a9e-3b7d-4c55-9a8e-2d4f0b1c7e93",
  "code": "UNSUPPORTED_VERSION",
  "request_id": "req-6f1c2a9e-3b7d-4c55-9a8e-2d4f0b1c7e93",
  "retryable": false,
  "supported": [
    "1",
    "2"
  ]
}
```


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