---
title: auth
sidebarTitle: auth
---

# `fastmcp.server.auth.auth`

## Classes

### `AccessToken` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L35" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


AccessToken that includes all JWT claims.


### `AuthProvider` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L41" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


Base class for all FastMCP authentication providers.

This class provides a unified interface for all authentication providers,
whether they are simple token verifiers or full OAuth authorization servers.
All providers must be able to verify tokens and can optionally provide
custom authentication routes.


**Methods:**

#### `verify_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L68" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
verify_token(self, token: str) -> AccessToken | None
```

Verify a bearer token and return access info if valid.

All auth providers must implement token verification.

**Args:**
- `token`: The token string to validate

**Returns:**
- AccessToken object if valid, None if invalid or expired


#### `get_routes` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L81" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_routes(self, mcp_path: str | None = None, mcp_endpoint: Any | None = None) -> list[Route]
```

Get the routes for this authentication provider.

Each provider is responsible for creating whatever routes it needs:
- TokenVerifier: typically no routes (default implementation)
- RemoteAuthProvider: protected resource metadata routes
- OAuthProvider: full OAuth authorization server routes
- Custom providers: whatever routes they need

**Args:**
- `mcp_path`: The path where the MCP endpoint is mounted (e.g., "/mcp")
- `mcp_endpoint`: The MCP endpoint handler to protect with auth

**Returns:**
- List of routes for this provider, including protected MCP endpoints if provided


#### `get_middleware` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L121" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_middleware(self) -> list
```

Get HTTP application-level middleware for this auth provider.

**Returns:**
- List of Starlette Middleware instances to apply to the HTTP app


### `TokenVerifier` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L154" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


Base class for token verifiers (Resource Servers).

This class provides token verification capability without OAuth server functionality.
Token verifiers typically don't provide authentication routes by default.


**Methods:**

#### `verify_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L175" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
verify_token(self, token: str) -> AccessToken | None
```

Verify a bearer token and return access info if valid.


### `RemoteAuthProvider` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L180" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


Authentication provider for resource servers that verify tokens from known authorization servers.

This provider composes a TokenVerifier with authorization server metadata to create
standardized OAuth 2.0 Protected Resource endpoints (RFC 9728). Perfect for:
- JWT verification with known issuers
- Remote token introspection services
- Any resource server that knows where its tokens come from

Use this when you have token verification logic and want to advertise
the authorization servers that issue valid tokens.


**Methods:**

#### `verify_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L221" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
verify_token(self, token: str) -> AccessToken | None
```

Verify token using the configured token verifier.


#### `get_routes` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L225" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_routes(self, mcp_path: str | None = None, mcp_endpoint: Any | None = None) -> list[Route]
```

Get OAuth routes for this provider.

Creates protected resource metadata routes and optionally wraps MCP endpoints with auth.


### `OAuthProvider` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L255" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


OAuth Authorization Server provider.

This class provides full OAuth server functionality including client registration,
authorization flows, token issuance, and token verification.


**Methods:**

#### `verify_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L311" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
verify_token(self, token: str) -> AccessToken | None
```

Verify a bearer token and return access info if valid.

This method implements the TokenVerifier protocol by delegating
to our existing load_access_token method.

**Args:**
- `token`: The token string to validate

**Returns:**
- AccessToken object if valid, None if invalid or expired


#### `get_routes` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/auth.py#L326" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_routes(self, mcp_path: str | None = None, mcp_endpoint: Any | None = None) -> list[Route]
```

Get OAuth authorization server routes and optional protected resource routes.

This method creates the full set of OAuth routes including:
- Standard OAuth authorization server routes (/.well-known/oauth-authorization-server, /authorize, /token, etc.)
- Optional protected resource routes
- Protected MCP endpoints if provided

**Returns:**
- List of OAuth routes

