ExMCP.Authorization.ClientRegistration (ex_mcp v0.10.0)

This module implements the standard MCP specification.

Dynamic Client Registration for OAuth 2.1.

Implements RFC 7591 (OAuth 2.0 Dynamic Client Registration Protocol) to allow MCP clients to register themselves with authorization servers at runtime.

Example

# Register a new client
{:ok, client_info} = ExMCP.Authorization.ClientRegistration.register_client(%{
  registration_endpoint: "https://auth.example.com/register",
  client_name: "My MCP Client",
  redirect_uris: ["https://localhost:8080/callback"],
  grant_types: ["authorization_code"],
  response_types: ["code"],
  scope: "mcp:read mcp:write"
})

# Use the returned client_id and client_secret for authorization flows

Summary

Types

client_information()

registration_request()

Functions

get_client_information(registration_client_uri, registration_access_token)

Retrieves client information using a registration access token.

register_client(request)

Registers a new client with the authorization server.

update_client_information(registration_client_uri, registration_access_token, updates)

Updates client information using a registration access token.

Types

client_information()

@type client_information() :: %{
  client_id: String.t(),
  client_secret: String.t() | nil,
  client_secret_expires_at: integer() | nil,
  registration_access_token: String.t() | nil,
  registration_client_uri: String.t() | nil,
  client_name: String.t(),
  redirect_uris: [String.t()],
  grant_types: [String.t()],
  response_types: [String.t()],
  scope: String.t()
}

registration_request()

@type registration_request() :: %{
  :registration_endpoint => String.t(),
  :client_name => String.t(),
  :redirect_uris => [String.t()],
  :grant_types => [String.t()],
  :response_types => [String.t()],
  :scope => String.t(),
  optional(:token_endpoint_auth_method) => String.t(),
  optional(:client_uri) => String.t() | nil,
  optional(:logo_uri) => String.t() | nil,
  optional(:contacts) => [String.t()] | nil,
  optional(:tos_uri) => String.t() | nil,
  optional(:policy_uri) => String.t() | nil,
  optional(:software_id) => String.t() | nil,
  optional(:software_version) => String.t() | nil
}

Functions

get_client_information(registration_client_uri, registration_access_token)

@spec get_client_information(String.t(), String.t()) ::
  {:ok, client_information()} | {:error, term()}

Retrieves client information using a registration access token.

This allows clients to read their current registration information from the authorization server.

register_client(request)

@spec register_client(registration_request()) ::
  {:ok, client_information()} | {:error, term()}

Registers a new client with the authorization server.

This implements the client registration flow from RFC 7591, sending client metadata to the registration endpoint and receiving client credentials in response.

update_client_information(registration_client_uri, registration_access_token, updates)

@spec update_client_information(String.t(), String.t(), map()) ::
  {:ok, client_information()} | {:error, term()}

Updates client information using a registration access token.

This allows clients to modify their registration information at the authorization server.