> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.duuo.cooperators.ca/prefill-api-guide/authorization/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.duuo.cooperators.ca/_mcp/server.

# Authorization

All partner-facing Prefill APIs use OAuth 2.0 with the Client Credentials grant type. This is a system-to-system flow. No customer or browser redirect is involved. Your backend systems authenticate directly with Co‑operators using credentials issued during onboarding.

## Credentials

During onboarding, Co‑operators will issue:

* `client_id`

* `client_secret`

Store these credentials securely in a server-side secrets manager or equivalent credential store.

Do not expose credentials in:

* Client-side code.

* Browser or mobile requests.

* URL parameters.

* Application logs.

* Analytics or monitoring payloads.

Credentials may expire or require renewal based on your partner agreement.

## Requesting an Access Token

Before calling any Prefill API, your system must obtain a Bearer token.

```
Endpoint: POST https://{{base_url}}/api/1.0/oauth2/access_token
Headers:
Content-Type: application/x-www-form-urlencoded
Authorization: Basic <base64(client_id:client_secret)> 
Body:
grant_type=client_credentials

```

Example response:

```json
{
  "access_token": "eyJhbGci...token",
  "expires_in": 3600,
  "token_type": "Bearer"
}

```

## Using the Token

Include the token in the Authorization header of every subsequent API call:

```
Authorization: Bearer <access_token>

```

## Token Lifecycle

Tokens expire after 1 hour (3600 seconds). When a token expires, request a new one using the same client credentials flow. To avoid interruptions, implement token caching and pre-emptive renewal (e.g., renew when less than 5 minutes of lifetime remain rather than waiting for a 401 response).

## Security Requirements

* All API traffic must use HTTPS/TLS. Unencrypted connections are rejected.

* Client secret must never appear in client-side code, browser requests, URL parameters, or application logs.

* Credentials are stored encrypted server-side and only decrypted at the time of authentication.

* IP allow-listing may be required depending on your partner agreement. Confirm with your Co‑operators integration contact during onboarding.


## API Docs

- [Token API](https://docs.duuo.cooperators.ca/prefill-api-guide/authorization/token-api.md): Authorization

## OpenAPI Specification

- [OpenAPI JSON](https://docs.duuo.cooperators.ca/openapi.json): raw OpenAPI 3.1 specification for this API, JSON format
- [OpenAPI YAML](https://docs.duuo.cooperators.ca/openapi.yaml): raw OpenAPI 3.1 specification for this API, YAML format