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

# Overview

> The Authentication API issues OAuth2 access tokens for Hellgate Cloud Platform services.

export const RunInPostman = ({uid, title, workspace, children}) => <Card title={title || "Run in Postman"} icon="right-from-bracket" href={`https://www.postman.com/sf-hellgate/${workspace}/collection/${uid}`}>
    {children}
  </Card>;

The Authentication API issues the **OAuth2 access tokens** used to call Hellgate Cloud Platform services. You
exchange a **client ID** and **client secret** for a token using the **client-credentials** grant, then send
the token as a bearer token on each request.

<RunInPostman uid="32200380-fa48231c-9971-4d1d-9d6d-371bde34c900" workspace="hellgate-documentation" title="Platform API in Postman">
  The platform-level APIs — OAuth2, Account Information, and Admin. Duplicate the **Dedicated instance —
  template** environment and fill in your client credentials. **OAuth2 → Request an access token** is the
  token endpoint documented here, sent as a real request; the product collections in this workspace get
  their tokens the same way, from a pre-configured Authorization tab.
</RunInPostman>

## Token endpoint

The token endpoint is hosted at `https://auth.eu1.hellgate.cloud`.

## Authentication

Send your client ID and client secret to the token endpoint using **HTTP Basic** authentication. The
**Request an access token** operation describes the request and response in full.

Tokens are scoped to an **audience** — the service instance they may call — and carry the **scopes** that gate
individual endpoints. The `audience` and `scope` parameters are both required on every token request; there
are no defaults, and each must fall within the limits provisioned on your client. For how a specific product
validates the token and which scopes and audience it requires, see that product's access guide — for example,
[Specter Authentication](/products/specter/authentication).