List all enabled tools from providers. Overrides Provider.list_tools() to add visibility filtering, auth filtering, and middleware ex

Look up a cached verification result. Returns: ``(True, AccessToken)`` on a cache hit, ``(False, None)`` on a miss or

Create a Tool from a function.

Add a server-level transform. Server-level transforms are applied after all providers are aggregated. They transform tools, resources

Mount another FastMCP server on this server with an optional namespace. Unlike importing (with import_server), mounting establishes a dynamic

List all enabled resources from providers. Overrides Provider.list_resources() to add visibility filtering, auth filtering, and middl

Send a `DEBUG`-level message to the connected MCP Client. Messages sent to Clients are also logged to the `fastmcp.server.context.to_client`

Wait for and return the task result. Must be implemented by subclasses to return the appropriate result type.

Store a *successful* verification result. Only successful verifications should be cached. Failures (inactive tokens, missing scopes,

Disable components matching all specified criteria. Adds a visibility transform that marks matching components as disabled. Component

Get a logger nested under FastMCP namespace. Args: name: the name of the logger, which will be prefixed with 'FastMCP.' Returns:

Convert JSON schema to appropriate Python type with validation. Args: schema: A JSON Schema dictionary defining the type structure and va

List all enabled prompts from providers. Overrides Provider.list_prompts() to add visibility filtering, auth filtering, and middlewar

Add a provider for dynamic tools, resources, and prompts. Providers are queried in registration order. The first provider to return a

Decode cursor from an opaque string. Raises: ValueError: If the cursor is invalid or malformed.

Get a prompt by name, filtering disabled prompts. Overrides Provider.get_prompt() to add visibility filtering after all transforms (i

List all enabled resource templates from providers. Overrides Provider.list_resource_templates() to add visibility filtering, auth fi

Wait for task to reach a specific state or complete. Uses event-based waiting when notifications are available (fast), with fallback

Generate a test JWT token using symmetric key for testing purposes. Args: subject: Subject claim (usually user ID)

Create a Starlette app using the specified HTTP transport. Args: path: The path for the HTTP endpoint middleware: A l

Send a `WARNING`-level message to the connected MCP Client. Messages sent to Clients are also logged to the `fastmcp.server.context.to_client

Encode cursor state to an opaque string.

Get a tool by name, filtering disabled tools. Overrides Provider.get_tool() to add visibility filtering after all transforms (includi

Mock token verification.

Create a test access token.

Reset all state for next test.

Compress and optimize a JSON schema for MCP compatibility. Args: schema: The schema to compress prune_params: List of parame

Delegate route creation to the server.

Check if a version matches this spec. Args: version: The version to check, or None for unversioned. match_none: Wheth

Combines parameter and request body schemas into a single schema. Handles parameter name collisions by adding location suffixes. Also ret

Add two numbers.

Read the resource content. Subclasses implement this to return resource data. Supported return types: - str: Text content

Run auth checks with AND logic.

Add a tool to the server. The tool function can optionally request a Context object by adding a parameter with the Context type annot

Convert an OpenAPI schema to JSON Schema format. This is a clean, systematic approach that: 1. Removes OpenAPI-specific fields 2. Co

Create a copy of the component.

Send a `ERROR`-level message to the connected MCP Client. Messages sent to Clients are also logged to the `fastmcp.server.context.to_client`

Format the universal name for a backend tool: ``<hash>_<local_name>``.

Render the prompt with arguments. Subclasses must implement this method. Return one of: - str: Wrapped as single user Message

Start a FastMCP server as an asyncio task for in-process async testing. This is the recommended way to test FastMCP servers. It runs the ser

Overload: With result_type, returns SamplingResult[ResultT].

Get the FastMCP access token from the current context. This function first tries to get the token from the current HTTP request's scope, whic

Create a FastMCP proxy server for the given target. This is the recommended way to create a proxy server. For lower-level control, use `FastM

Enable components matching all specified criteria. Adds a visibility transform that marks matching components as enabled. Later trans

TypeAdapters are heavy objects, and in an application context we'd typically create them once in a global scope and reuse them as often as po

Extract information from a FastMCP instance into a dataclass. This function automatically detects whether the instance is FastMCP v1.x or v2.x

Securely check if a URI matches an allowed pattern with wildcard support. This function parses both the URI and pattern as URLs, comparing each

Parse scopes from environment variables or settings values. Accepts either a JSON array string, a comma- or space-separated string, a list of

Send a ping request.

Temporarily override FastMCP setting values. Args: **kwargs: The settings to override, including nested settings. Example:

Cancel this task, transitioning it to cancelled state. Sends a tasks/cancel protocol request. The server will attempt to halt executi

Create a resource from the template with the given parameters. The base implementation does not support background tasks. Use Functio

Generate an RSA key pair for testing. Returns: RSAKeyPair: Generated key pair

Import the MCP objects from another FastMCP server into this one, optionally with a given prefix. .. deprecated::

Override to preserve _backend_name when name changes.

Create a FastMCP proxy server for the given backend. .. deprecated:: Use :func:`fastmcp.server.create_proxy` instead.

Import a Python file as a module. If the file is part of a package (directory has __init__.py), imports it as a proper package member (relati

Send a `INFO`-level message to the connected MCP Client. Messages sent to Clients are also logged to the `fastmcp.server.context.to_client` l

Check if component is enabled. Returns True if: - No visibility mark exists (default is enabled) - Visibility mark is True Returns F

Return an instance of the StreamableHTTP server app. Args: server: The FastMCP server instance streamable_http_path: Path for Str

Send a log message to the client. Messages sent to Clients are also logged to the `fastmcp.server.context.to_client` logger with a level of `

Create a mock tool for testing.

Extract a string result from a ToolResult.

Set the access token in the auth context var.

Get current task status. If server executed immediately, returns synthetic completed status. Otherwise queries the server for current

Await a coroutine while monitoring the session task for errors. When using HTTP transports, server errors (4xx/5xx) are raised in the

Build complete uv run command with environment args and command to execute. Args: command: Command to execute (e.g., ["fastmcp",

Require all of the given OAuth scopes.

Turn CLI inputs into something ``Client()`` accepts. Exactly one of ``server_spec`` or ``command`` should be provided. Resolution order for

Extract tool list from a ToolResult's structured content.

Get the meta information about the component. Returns a dict that always includes a `fastmcp` key containing: - `tags`: sorted list o

Match URI against template and extract both path and query parameters. Supports RFC 6570 URI templates: - Path params: `{var}`, `{var*}`

Parse a function's docstring into a summary and parameter descriptions. Tries Google, NumPy, and Sphinx parsers in order, using the first one tha

Parses an OpenAPI schema dictionary into a list of HTTPRoute objects using the openapi-pydantic library. Supports both OpenAPI 3.0.x and

Register a client locally When a client registers, we create a ProxyDCRClient that is more forgiving about validating redirect URIs,

Run the tool with arguments. This method is not implemented in the base Tool class and must be implemented by subclasses.

Verify a Clerk OAuth token via introspection and userinfo. Calls the introspection endpoint first to validate the token and retrieve