{"passport":{"unfragile":{"@version":"1.0","version":"2026-05","artifact":{"id":"awesome-fastmcp","slug":"fastmcp","name":"FastMCP","type":"mcp","url":"https://github.com/punkpeye/fastmcp","page_url":"https://unfragile.ai/fastmcp","categories":["mcp-servers"],"tags":[],"pricing":{"model":"open_source","free":true,"starting_price":null},"status":"active","verified":false},"capabilities":[{"id":"awesome-fastmcp__cap_0","uri":"capability://tool.use.integration.declarative.tool.registration.with.schema.validation","name":"declarative tool registration with schema validation","description":"Registers MCP tools via addTool() method with pluggable schema validation (Zod, ArkType, or Valibot) that automatically validates parameters before execution. FastMCP wraps the raw MCP SDK's tool handler registration, normalizing parameter validation and error handling across multiple validation libraries without requiring developers to write boilerplate protocol compliance code.","intents":["I want to expose a function as an MCP tool without manually writing JSON schema validators","I need parameter validation that works with my existing Zod/ArkType/Valibot schemas","I want to register multiple tools with consistent error handling and type safety"],"best_for":["TypeScript developers building MCP servers with type safety","teams standardizing on schema validation libraries across their stack"],"limitations":["Validation library must be installed separately; FastMCP does not bundle validators","Schema validation adds ~5-10ms per tool invocation for complex nested schemas","No built-in rate limiting or quota enforcement per tool"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","One of: Zod, ArkType, or Valibot installed in project"],"input_types":["function definition with typed parameters","schema validation library instance"],"output_types":["registered MCP tool handler","validation errors as MCP protocol responses"],"categories":["tool-use-integration","schema-validation"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_1","uri":"capability://tool.use.integration.resource.and.resource.template.registration.with.uri.based.loading","name":"resource and resource template registration with uri-based loading","description":"Registers static resources and dynamic resource templates via addResource() and addResourceTemplate() methods that map URIs to lazy-loaded content. Resources are identified by fixed URIs (e.g., 'file://config.json'), while templates use URI patterns (e.g., 'file://docs/{name}') with argument substitution. FastMCP handles URI parsing, argument extraction, and content normalization (text, image, audio) automatically.","intents":["I want to expose files or dynamic content as MCP resources without writing URI parsing logic","I need to serve parameterized resources where clients request 'file://docs/{docname}'","I want to lazy-load resource content only when clients request it"],"best_for":["MCP servers exposing file systems, documentation, or knowledge bases","teams building context-aware agents that need to retrieve documents by name or ID"],"limitations":["No built-in caching; repeated requests to same resource re-execute load() function","URI template argument validation relies on developer-provided schemas; no automatic type coercion","Large resources (>100MB) may cause memory issues if loaded entirely into memory"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","Resource content must be loadable synchronously or via async function"],"input_types":["URI string (fixed or template pattern)","async load function returning text/image/audio content","optional schema for template arguments"],"output_types":["MCP resource with URI and content","normalized content (text, image, audio MIME types)"],"categories":["tool-use-integration","memory-knowledge"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_10","uri":"capability://safety.moderation.error.handling.and.protocol.compliance","name":"error handling and protocol compliance","description":"Automatically converts exceptions and validation errors from tool/resource/prompt handlers into MCP-compliant error responses. FastMCP catches exceptions, formats error messages, and returns them as MCP error objects without requiring developers to manually implement error serialization. Validation errors from schema validators are automatically converted to MCP error responses.","intents":["I want exceptions in my tool handlers to be automatically converted to MCP error responses","I need validation errors to be returned as MCP-compliant error objects","I want consistent error handling across all tools without writing try-catch in each handler"],"best_for":["developers building robust MCP servers with consistent error handling","teams requiring MCP protocol compliance without manual error serialization","organizations needing detailed error messages for debugging"],"limitations":["Error messages are not sanitized; sensitive information may be exposed to clients","No built-in error categorization; all errors are treated equally","Stack traces are not included in error responses; debugging requires server logs"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript"],"input_types":["exceptions thrown from handlers","validation errors from schema validators"],"output_types":["MCP error response with error code and message"],"categories":["safety-moderation","automation-workflow"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_11","uri":"capability://automation.workflow.custom.http.routes.and.middleware.integration","name":"custom http routes and middleware integration","description":"Allows registration of custom HTTP routes alongside MCP protocol endpoints via custom route handlers. FastMCP exposes the underlying HTTP server, enabling developers to add Express-style middleware and custom routes for health checks, metrics, webhooks, or other HTTP endpoints. Custom routes coexist with MCP protocol handlers on the same server instance.","intents":["I want to add health check endpoints to my MCP server","I need to expose metrics or monitoring endpoints alongside MCP","I want to handle webhooks or other HTTP requests on the same server"],"best_for":["MCP servers deployed to cloud platforms requiring health checks","teams building observable MCP servers with metrics endpoints","developers integrating MCP servers with existing HTTP infrastructure"],"limitations":["Custom routes are only available with HTTP transport; not supported over stdio","No built-in middleware support; developers must implement middleware manually","Custom routes are not part of MCP protocol; clients cannot discover them"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","HTTP streaming transport (not stdio)"],"input_types":["HTTP method (GET, POST, etc.)","route path (string or regex)","route handler function"],"output_types":["HTTP response with status code and body"],"categories":["automation-workflow","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_12","uri":"capability://memory.knowledge.resource.roots.discovery.and.dynamic.root.updates","name":"resource roots discovery and dynamic root updates","description":"Manages resource roots (filesystem or URI prefixes) that clients can discover and subscribe to changes. FastMCP allows registration of resource roots and emits rootsChanged events when roots are added/removed. Clients can discover available roots and receive notifications of changes, enabling dynamic resource discovery without polling.","intents":["I want clients to discover what resource roots are available on my server","I need to notify clients when new resource roots become available","I want to support dynamic resource discovery without hardcoding root paths"],"best_for":["MCP servers with dynamic or user-specific resource roots","teams building file system or knowledge base servers with changing content","developers implementing resource discovery for LLM agents"],"limitations":["Root changes are not persisted; clients must re-discover roots after server restart","No built-in filtering or access control for roots; all clients see all roots","Root discovery is not real-time; clients must poll or wait for rootsChanged events"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript"],"input_types":["resource root URI (string)"],"output_types":["list of available resource roots","rootsChanged events when roots are added/removed"],"categories":["memory-knowledge","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_2","uri":"capability://tool.use.integration.prompt.registration.with.argument.substitution.and.content.completion","name":"prompt registration with argument substitution and content completion","description":"Registers MCP prompts via addPrompt() that accept arguments and return templated content with optional auto-completion suggestions. Prompts are identified by name and can include argument schemas for validation. FastMCP normalizes prompt execution, argument binding, and optional completion suggestions into MCP protocol responses.","intents":["I want to register reusable prompt templates that LLMs can invoke with arguments","I need to provide completion suggestions for prompt arguments (e.g., available document names)","I want to dynamically generate prompt content based on runtime arguments"],"best_for":["MCP servers providing domain-specific prompts to LLM clients","teams building agentic systems where prompts are first-class capabilities"],"limitations":["Prompt content is generated on-demand; no built-in caching of rendered prompts","Completion suggestions must be computed synchronously or via async function; large suggestion sets may impact latency","No versioning support for prompts; clients always receive latest version"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","Prompt load function must return string content"],"input_types":["prompt name (string identifier)","optional argument schema and values","optional completion function"],"output_types":["rendered prompt content (string)","optional completion suggestions (array of strings)"],"categories":["tool-use-integration","text-generation-language"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_3","uri":"capability://automation.workflow.stdio.and.http.streaming.transport.abstraction","name":"stdio and http streaming transport abstraction","description":"Abstracts MCP transport mechanisms via start() method that configures either StdioServerTransport (for local stdio-based clients) or HTTP streaming transport (for remote clients). FastMCP handles transport initialization, connection lifecycle, and message framing automatically. Developers specify transport type via configuration; FastMCP manages the underlying transport setup without exposing transport details.","intents":["I want to run an MCP server over stdio for local Claude Desktop integration","I need to expose an MCP server over HTTP for remote LLM clients","I want to support both stdio and HTTP transports from a single server implementation"],"best_for":["developers integrating with Claude Desktop or other stdio-based MCP clients","teams deploying MCP servers to cloud platforms (AWS Lambda, Vercel, etc.)","organizations needing both local and remote MCP server deployments"],"limitations":["HTTP streaming transport requires explicit port configuration; no automatic port discovery","stdio transport blocks on stdin; cannot multiplex multiple clients on single process","HTTP transport adds ~50-100ms latency per round-trip compared to stdio","No built-in TLS/SSL for HTTP transport; requires reverse proxy for production HTTPS"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","For HTTP transport: available port number (default 3000)"],"input_types":["transport type ('stdio' or 'http')","optional port number for HTTP transport","optional host binding for HTTP transport"],"output_types":["running MCP server listening on stdio or HTTP","connection events (connect, disconnect)"],"categories":["automation-workflow","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_4","uri":"capability://automation.workflow.per.client.session.management.with.authentication.context","name":"per-client session management with authentication context","description":"Manages per-client session state via FastMCPSession instances that track authentication context, client capabilities, and request lifecycle. Sessions are created on client connection and destroyed on disconnect. FastMCP automatically creates sessions and provides them to tool/resource/prompt handlers via Context parameter, enabling handlers to access session-specific state (authenticated user, client capabilities, request ID) without manual session lookup.","intents":["I want to track which user/client is making each request for authorization checks","I need to store per-client state (e.g., authenticated user, preferences) across multiple requests","I want to correlate requests with session IDs for logging and debugging"],"best_for":["MCP servers with per-user authorization or multi-tenant requirements","teams building stateful MCP servers that need to track client context","developers implementing OAuth or custom authentication flows"],"limitations":["Sessions are in-memory only; no built-in persistence across server restarts","No automatic session expiration; developers must implement timeout logic manually","Session state is not shared across multiple server instances; requires external state store for horizontal scaling"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","Optional: authentication function in ServerOptions"],"input_types":["client connection event","optional authentication credentials"],"output_types":["FastMCPSession instance with sessionId, authenticated user, client capabilities","session events (ready, error, rootsChanged)"],"categories":["automation-workflow","safety-moderation"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_5","uri":"capability://safety.moderation.authentication.and.authorization.with.oauth.discovery","name":"authentication and authorization with oauth discovery","description":"Integrates authentication via authenticate() function in ServerOptions and OAuth discovery via OAuth Discovery Endpoints. FastMCP calls authenticate() on client connection to validate credentials and attach user context to session. OAuth Discovery Endpoints allow clients to discover available OAuth providers and initiate OAuth flows. FastMCP handles OAuth proxy setup and token exchange automatically.","intents":["I want to require authentication before allowing clients to access my MCP server","I need to support OAuth flows so clients can authenticate via third-party providers","I want to expose available OAuth providers to clients via MCP discovery protocol"],"best_for":["MCP servers requiring user authentication or multi-tenant isolation","teams integrating with OAuth providers (Google, GitHub, etc.)","organizations building enterprise MCP servers with SSO requirements"],"limitations":["OAuth proxy requires additional infrastructure; not suitable for simple stdio-based servers","Token refresh logic must be implemented by developer; FastMCP does not auto-refresh tokens","OAuth Discovery Endpoints require explicit configuration; no automatic provider detection","No built-in support for SAML, OIDC, or other enterprise auth protocols"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","Optional: OAuth provider credentials (client ID, client secret)"],"input_types":["authenticate function accepting credentials","OAuth provider configuration (client ID, redirect URI, scopes)","optional OAuth Discovery Endpoint configuration"],"output_types":["authenticated session with user context","OAuth provider discovery response","OAuth token exchange response"],"categories":["safety-moderation","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_6","uri":"capability://automation.workflow.streaming.content.delivery.with.progress.reporting","name":"streaming content delivery with progress reporting","description":"Enables streaming of large content (text, images, audio) via streamContent() method in Context parameter, with optional progress reporting via reportProgress(). Streaming is implemented using MCP's streaming protocol, allowing clients to receive content incrementally without waiting for full response. Progress reporting provides real-time feedback on long-running operations.","intents":["I want to stream large files or generated content to clients without buffering entire response","I need to provide progress updates for long-running tool executions","I want to support real-time streaming of generated text or images"],"best_for":["MCP servers generating or retrieving large files (>10MB)","tools performing long-running operations (data processing, model inference)","applications requiring real-time feedback on operation progress"],"limitations":["Streaming is not supported over stdio transport; only HTTP streaming","Progress reporting is advisory only; clients may not display progress UI","Large streams may cause memory pressure if client cannot consume fast enough","No built-in backpressure handling; server may buffer data if client is slow"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","HTTP streaming transport (not stdio)"],"input_types":["content type (text, image, audio)","content data (string, Buffer, or stream)","optional progress callback"],"output_types":["streamed content chunks","progress events (optional)"],"categories":["automation-workflow","data-processing-analysis"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_7","uri":"capability://data.processing.analysis.content.normalization.for.text.image.and.audio","name":"content normalization for text, image, and audio","description":"Automatically normalizes content returned from tools, resources, and prompts into MCP-compliant formats via helper functions (imageContent(), audioContent(), textContent()). Handles MIME type detection, encoding (base64 for binary), and protocol compliance. Developers call these helpers instead of manually constructing content objects.","intents":["I want to return images from tools without manually base64-encoding and setting MIME types","I need to return audio content from resources with correct MIME type headers","I want to ensure all content I return is MCP protocol-compliant"],"best_for":["MCP servers returning multi-modal content (text, images, audio)","developers unfamiliar with MCP content format requirements","teams standardizing on content normalization across multiple servers"],"limitations":["MIME type detection is basic; may not correctly identify all content types","Base64 encoding adds ~33% size overhead for binary content","No built-in compression; large images/audio are not compressed before transmission"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript"],"input_types":["text string, image Buffer/path, or audio Buffer/path","optional MIME type override"],"output_types":["MCP-compliant content object with type, mimeType, and data fields"],"categories":["data-processing-analysis","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_8","uri":"capability://automation.workflow.request.context.and.logging.with.request.id.tracking","name":"request context and logging with request id tracking","description":"Provides Context object to all tool/resource/prompt handlers containing requestId, sessionId, log() method, and reportProgress() method. Context enables structured logging and request tracing without requiring developers to manually pass context through function signatures. Log messages are associated with request ID for correlation.","intents":["I want to log from tool handlers with automatic request ID correlation","I need to track which session/client made each request for debugging","I want structured logging without manually passing context through function parameters"],"best_for":["developers building MCP servers with observability requirements","teams implementing request tracing and debugging workflows","organizations needing audit logs of MCP server activity"],"limitations":["Log output format is not configurable; logs are written to stdout/stderr","No built-in log aggregation; logs are not persisted or sent to external services","Request ID is generated by FastMCP; no support for custom request ID schemes"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript"],"input_types":["Context object injected into handler functions"],"output_types":["log messages with request ID and session ID","progress events with request ID"],"categories":["automation-workflow","data-processing-analysis"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"awesome-fastmcp__cap_9","uri":"capability://automation.workflow.cli.tool.registration.and.execution","name":"cli tool registration and execution","description":"Registers system CLI commands as MCP tools via addTool() with automatic argument parsing and execution. FastMCP handles shell command invocation, output capture, and error handling. Developers specify command name, arguments, and optional working directory; FastMCP executes the command and returns stdout/stderr as tool result.","intents":["I want to expose system CLI commands as MCP tools without writing shell execution code","I need to run shell scripts or external programs from MCP tools","I want to capture and return CLI output as tool results"],"best_for":["MCP servers wrapping existing CLI tools or scripts","developers building integration layers between LLMs and system commands","teams automating infrastructure or DevOps tasks via MCP"],"limitations":["No built-in shell injection protection; developers must validate/sanitize arguments","Command execution is synchronous; long-running commands block the handler","No timeout enforcement; commands may hang indefinitely","Output is captured entirely in memory; large outputs may cause memory issues"],"requires":["Node.js 18+","TypeScript 4.7+ or JavaScript","CLI command must be available in system PATH or specified as absolute path"],"input_types":["command name (string)","command arguments (array of strings)","optional working directory"],"output_types":["stdout as string","stderr as string","exit code as number"],"categories":["automation-workflow","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0}],"trust":{"score":28,"verified":false,"data_access_risk":"high","permissions":["Node.js 18+","TypeScript 4.7+ or JavaScript","One of: Zod, ArkType, or Valibot installed in project","Resource content must be loadable synchronously or via async function","HTTP streaming transport (not stdio)","Prompt load function must return string content","For HTTP transport: available port number (default 3000)","Optional: authentication function in ServerOptions","Optional: OAuth provider credentials (client ID, client secret)","CLI command must be available in system PATH or specified as absolute path"],"failure_modes":["Validation library must be installed separately; FastMCP does not bundle validators","Schema validation adds ~5-10ms per tool invocation for complex nested schemas","No built-in rate limiting or quota enforcement per tool","No built-in caching; repeated requests to same resource re-execute load() function","URI template argument validation relies on developer-provided schemas; no automatic type coercion","Large resources (>100MB) may cause memory issues if loaded entirely into memory","Error messages are not sanitized; sensitive information may be exposed to clients","No built-in error categorization; all errors are treated equally","Stack traces are not included in error responses; debugging requires server logs","Custom routes are only available with HTTP transport; not supported over stdio","builder identity is not verified yet","no observed match outcomes yet"],"rank_breakdown":{"adoption":0.05,"quality":0.35,"ecosystem":0.39999999999999997,"match_graph":0.25,"freshness":0.52,"weights":{"adoption":0.25,"quality":0.25,"ecosystem":0.15,"match_graph":0.23,"freshness":0.12}},"observed_outcomes":{"matches":0,"success_rate":0,"avg_confidence":0,"top_intents":[],"last_matched_at":null},"maintenance":{"status":"active","updated_at":"2026-06-17T09:51:03.039Z","last_scraped_at":"2026-05-03T14:00:18.053Z","last_commit":null},"community":{"stars":null,"forks":null,"weekly_downloads":null,"model_downloads":null,"model_likes":null}},"distribution":{"claim_url":"https://unfragile.ai/submit?claim=fastmcp","compare_url":"https://unfragile.ai/compare?artifact=fastmcp"}},"signature":"DnSw8nCuDqGlERaZWP8/ZTShtylOYpa+l66bR8ani9AkLg/Bq4PBP1ud/al0tGuoq+mN1UiM5DCwG4qEqsUDBw==","signedAt":"2026-06-22T04:05:05.775Z","signedBy":"unfragile.ai","version":1},"_links":{"self":"https://unfragile.ai/api/v1/passport/fastmcp","artifact":"https://unfragile.ai/fastmcp","verify":"https://unfragile.ai/api/v1/verify?slug=fastmcp","publicKey":"https://unfragile.ai/api/v1/trust-passport-public-key","spec":"https://unfragile.ai/trust","schema":"https://unfragile.ai/schema.json","docs":"https://unfragile.ai/docs"}}