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

# Authentication

> Authenticate public API requests with Parsimmon API keys.

Parsimmon authenticates public API requests with API keys.

API keys use environment-specific prefixes:

* `psk_live_` for live traffic.
* `psk_test_` for test and development traffic.

Pass the key in the `Authorization` header:

```bash theme={null}
Authorization: Bearer psk_test_...
```

Create API keys in Studio. The full secret is shown once when the key is created. Store it in your secret manager before leaving the page; Parsimmon only stores and displays the key prefix after creation.

Keys carry scopes. A key with the `parse` scope can call parse endpoints. A key with the `extract` scope can call extract endpoints. Use the narrowest scope your integration needs.

Requests without a valid bearer token return the standard error envelope:

```json theme={null}
{
  "error": {
    "code": "unauthenticated",
    "message": "Authentication required.",
    "details": {}
  }
}
```