OAuth Flow

Authorize your Along account using OAuth 2.0 PKCE to connect to Claude, ChatGPT, or any MCP client.

Along uses OAuth 2.0 with PKCE (Proof Key for Code Exchange) — no client secret required. This is the standard flow used by Claude and ChatGPT when you add a new MCP connector. Your credentials never leave Along’s authorization server.

Authorization server metadata

Any MCP client can discover Along’s OAuth endpoints by fetching the well-known metadata document:

GET /.well-known/oauth-authorization-server

Response:

{
  "issuer": "https://along-api-qrd5m37v3a-ey.a.run.app",
  "authorization_endpoint": "https://along-api-qrd5m37v3a-ey.a.run.app/oauth/authorize",
  "token_endpoint": "https://along-api-qrd5m37v3a-ey.a.run.app/oauth/token",
  "registration_endpoint": "https://along-api-qrd5m37v3a-ey.a.run.app/oauth/register",
  "response_types_supported": ["code"],
  "grant_types_supported": ["authorization_code", "refresh_token"],
  "token_endpoint_auth_methods_supported": ["none"],
  "code_challenge_methods_supported": ["S256"],
  "scopes_supported": ["vault:read", "vault:write"]
}

Scopes

Scope	Description
vault:read	Read access to the Safe’s knowledge graph. Required for all MCP queries.
vault:write	Write access. Reserved for future use — vault:read is sufficient for all current MCP tools.

OAuth flow

1. Discovery

   The MCP client fetches /.well-known/oauth-authorization-server to discover the authorization and token endpoints. This step is automatic for clients like Claude and ChatGPT.

2. Authorization request

   The client redirects you to GET /oauth/authorize with the following parameters:

   Parameter	Required	Description
   response_type	Yes	Must be code
   client_id	Yes	Your client ID, obtained from registration or auto-assigned
   redirect_uri	Yes	Must match a registered URI or a known pattern (claude.ai, chatgpt.com, localhost)
   code_challenge	Yes	SHA-256 of your code_verifier, base64url-encoded
   code_challenge_method	Yes	Must be S256
   scope	No	Defaults to vault:read
   state	No	CSRF token; returned unchanged in the callback
   resource	No	The MCP endpoint URL, e.g. https://along-api-qrd5m37v3a-ey.a.run.app/mcp/v1

   Example authorization URL:

   GET /oauth/authorize
     ?response_type=code
     &client_id=along_abc123
     &redirect_uri=https%3A%2F%2Fclaude.ai%2Fapi%2Fmcp%2Fauth_callback
     &code_challenge=E9Melhoa2OwvFrEMTJguCHaoeK1t8URWbuGJSstw-cM
     &code_challenge_method=S256
     &scope=vault%3Aread
     &state=xyz
   
3. User consent

   Along redirects you to the Along app consent page. Log in with your Along account and optionally select a Safe to associate with this connection. Once you approve, Along returns an authorization code to the redirect_uri.

   The authorization code expires in 10 minutes.

4. Token exchange

   The client sends the authorization code to the token endpoint to receive access and refresh tokens:

   POST /oauth/token
   Content-Type: application/x-www-form-urlencoded
   
   grant_type=authorization_code
   &code=<authorization_code>
   &redirect_uri=https://claude.ai/api/mcp/auth_callback
   &code_verifier=<your_code_verifier>
   &client_id=along_abc123
   

   Response:

   {
     "access_token": "avo_...",
     "token_type": "Bearer",
     "expires_in": 3600,
     "refresh_token": "avr_...",
     "scope": "vault:read"
   }
   
5. Using the token

   Include the access token as a Bearer token in all MCP requests:

   POST /mcp/v1
   Authorization: Bearer avo_...
   Content-Type: application/json
   

Token lifetimes

Token	Lifetime
Access token	1 hour (expires_in: 3600)
Refresh token	90 days
Authorization code	10 minutes

Refreshing tokens

When an access token expires, the client exchanges the refresh token for a new access token and refresh token pair:

POST /oauth/token
Content-Type: application/x-www-form-urlencoded

grant_type=refresh_token
&refresh_token=avr_...
&client_id=along_abc123

The response has the same shape as the initial token response, with new access_token and refresh_token values. The old refresh token is revoked immediately after use.

Client registration

For custom integrations that aren’t Claude or ChatGPT, register your client before starting the OAuth flow:

POST /oauth/register
Content-Type: application/json

{
  "redirect_uris": ["https://myapp.example.com/oauth/callback"],
  "client_name": "My Integration",
  "grant_types": ["authorization_code"],
  "token_endpoint_auth_method": "none"
}

Response:

{
  "client_id": "along_...",
  "client_name": "My Integration",
  "redirect_uris": ["https://myapp.example.com/oauth/callback"],
  "grant_types": ["authorization_code"],
  "token_endpoint_auth_method": "none"
}

Use the returned client_id in all subsequent authorization requests.

Claude and ChatGPT auto-register as clients when they initiate the OAuth flow — you don’t need to pre-register for those integrations.