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

# API resource index

> Give an agent one compact, public index of PlainRouter's Conversion API, authentication, OpenAPI, MCP, and discovery resources.

Use the API resource index when an agent needs a short, heading-led map of
PlainRouter's developer surfaces before choosing an interface or credential.
The index is public, requires no authentication, and does not perform any
product action.

Fetch the canonical resource from:

```text theme={null}
https://plainrouter.com/api/llms.txt
```

This Mintlify explanation is also available as a Markdown page at
`/reference/api-resource-index.md`.

## What does the index contain?

The index identifies these current entry points:

| Resource                         | Use it for                                                                              |
| -------------------------------- | --------------------------------------------------------------------------------------- |
| Conversion API base URL          | Send authenticated Signals requests.                                                    |
| API documentation                | Read the server-side request, authentication, and retry contract.                       |
| Versioning policy                | Check compatibility, deprecation, and sunset behavior.                                  |
| Signed OpenAPI specification     | Inspect schemas or generate a compatible client.                                        |
| Authentication guide             | Select the correct credential for REST, SDK, CLI, MCP, or management discovery.         |
| Webhook guide                    | Verify supported webhook requests before accepting them.                                |
| RFC 9727 API catalog             | Follow typed relations to API, MCP, documentation, specification, and status resources. |
| OAuth metadata and MCP manifests | Discover the protected resource and connect an approved agent client.                   |

The response uses `text/plain; charset=UTF-8`. Its Markdown-compatible headings
and links allow an agent to parse the index without rendering HTML.

## Which discovery resource should I use?

* Start with this index when you need a readable inventory.
* Use the [RFC 9727 API catalog](/docs/reference/api-catalog) when software needs
  typed link relations.
* Use the [signed OpenAPI specification](/docs/reference/conversion-api#use-the-signed-openapi-contract)
  when software needs operation and schema details.
* Use [Authentication and clients](/docs/auth) before sending a
  credential.

<Warning>
  Discovery does not grant access. Never infer a credential, workspace, Meta ad
  account, permission, or approval from a public resource.
</Warning>