Convert schema to appropriate Python type.

Configure logging for FastMCP. Args: logger: the logger to configure level: the log level to use rich_kwargs: the pa

Try to consume tokens from the bucket. Args: tokens: Number of tokens to consume Returns: True if tokens wer

Helper to create a FastMCP server with OpenAPIProvider.

Create a complete HTML page with FastMCP styling. Args: content: HTML content to place inside the page title: Page title

Create an OAuth proxy with specified storage.

Return an instance of the SSE server app. Args: server: The FastMCP server instance message_path: Path for SSE messages s

Deduplicate components by key, keeping highest version. Groups components by key, selects the highest version from each group, and injects av

Default handler that properly routes server log messages to appropriate log levels.

Extract output schema from OpenAPI responses for use as MCP tool output schema. This function finds the first successful response (200, 201,

Format FastMCPInfo as FastMCP-specific JSON. This includes FastMCP-specific fields like tags, enabled, annotations, etc.

Create a FastMCP server from an OpenAPI specification. Args: openapi_spec: OpenAPI schema as a dictionary cl

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

Generate JSON schema for fastmcp.json files. This is used to create the schema file that IDEs can use for validation and auto-completion.

Get prompt by transformed name with all transforms applied. Note: This method does NOT filter disabled components. The Server (FastMC

Get the authorization scope for task isolation. Returns the raw scope identifier for the current access token, or ``None`` when no auth conte

Fetch the real tool catalog, bypassing this transform. The result is deduplicated by name so that only the highest version of each to

Creates a standardized error response for phue operations.

Check if a host is a loopback address. Per RFC 8252 §7.3, loopback covers the whole reserved loopback range, not just the two familiar litera

A minimal FastMCP access token for auth-scoped task tests.

Context manager to mock AWS Cognito OIDC discovery endpoint.

Create a new mock middleware context.

Normalize a timeout value to a timedelta. Args: value: Timeout value as int/float (seconds), timedelta, or None Returns: tim

Start ping task on first message from a connection.

Parse YAML frontmatter from markdown content. Args: content: Markdown content potentially starting with --- Returns: Tuple o

Prepare a FastMCP project by creating a persistent uv environment. This command creates a persistent uv project with all dependencies installed:

Prepare the Python environment using uv. Args: output_dir: Directory where the persistent uv project will be created.

Read a client's per-request extension opt-in from the request `_meta`. SEP-2133 extensions negotiate per request: the client repeats its extensio

Fetch a new access token using a refresh token. If the server does not rotate the refresh token, the previous one is injected into th

Registers all methods marked with @mcp_prompt with the FastMCP server. Args: mcp_server: The FastMCP server instance to register

Registers all methods marked with @mcp_resource with the FastMCP server. Args: mcp_server: The FastMCP server instance to registe

Resolve the effective ``by_alias`` setting for serializing *value*. Pydantic's low-level serialization helpers (``to_json``, ``to_jsonable_py

Run an MCP server or connect to a remote one. The server can be specified in several ways: 1. Module approach: "server.py" - runs the module

Run an ASGI application's lifespan, driving the protocol as a real server does. The application's lifespan runs inside a dedicated task for the w

Run a Python module directly using ``python -m <module>``. When ``-m`` is used, the module manages its own server startup. No server-object d

Bind the default verifier's audience to this server's resource URL.

Set up HTTP routes for enabling/disabling tools, resources, and prompts. Args: server: The FastMCP server instance. path: Base pa

Download all available skills from a server. Args: client: Connected FastMCP client target_dir: Directory where skill folders wil

Validate a hosted CIMD document. Fetches the document from the given URL and validates: - URL is valid CIMD URL (HTTPS, non-root path) -

Get the current FastMCP Context instance. This dependency provides access to the active FastMCP Context for the current MCP operation (tool/r

Get the current FastMCP server instance. This dependency provides access to the active FastMCP server. Returns: A dependency that re

Initialize a FastMCPProvider. Args: server: The FastMCP server to wrap.

Initialize the multi-auth provider. Args: server: Optional auth provider (e.g., OAuthProxy) that owns routes and

Read the string value a client accepted for `key` (test helper).

Apply pagination to items, raising MCPError for invalid cursors. If page_size is None, returns all items without pagination.

Convert MCP AudioContent to OpenAI input_audio content part.

Issue a handshake-era `roots/list` from a backend server. `Context` has no `list_roots()`: server-initiated requests are not part of FastMCP'

Serve one of the cacheable list verbs through the response cache. Mirrors the SDK Client's `_cached_fetch`: cursorless `use` calls are served

Convert a sequence to a set, defaulting to an empty set if None.

Return secure cookie name for HTTPS, fallback for HTTP development.

Create a client factory from the given target. Internal helper that handles the session strategy based on the target type: - Connected Client

Create a default httpx client from the OpenAPI spec's server URL.

Ensure skills are discovered, rediscovering if reload is enabled.

Extract CSRF token from HTML form.

Extract the list of names from a call_tool ToolResult.

Resolves a schema and returns it as a dictionary.

Get the path to the version cache file.

Gets a client instance by calling the sync or async factory.

Get client identifier for rate limiting.

Get the highest version from successful non-None results. Used for versioned components where we want the highest version across all

Fetch key from JWKS with simple caching and SSRF protection.

Get or create a per-token refresh lock, evicting LRU entries when at capacity.

Return the advertised scopes, discovering them lazily if enabled. The result of a successful discovery is cached for the provider's l

Read the stored hash from tool meta, or compute from app name + tool name.

Handle callback from upstream IdP and forward to client. This implements the DCR-compliant callback forwarding: 1. Receive IdP callba

Build a fixed-length SHA-256 cache key from request-derived input.

List all tools from the remote server.

Create a tool with a specific version for testing.

Redis hash mapping a leg's surfaced keys back to the tool's own keys.

Configure *mock_client* to return a successful GitHub user + scopes response.

Delay before the next poll, plus the backoff for the round after. With no status notifications on the modern protocol, polling is the only si