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Uses transport-agnostic architecture supporting stdio, HTTP, and SSE transports, with automatic message serialization/deserialization and request-response correlation via message IDs. Handles concurrent requests with promise-based async/await patterns and built-in error propagation.","intents":["I need to expose my tools and resources to Claude or other MCP clients without building custom protocol handling","I want to create a server that multiple AI applications can connect to simultaneously","I need bidirectional communication where the server can also make requests to clients"],"best_for":["TypeScript/Node.js developers building tool integrations for Claude","Teams creating standardized tool interfaces across multiple AI applications","Developers migrating from REST APIs to MCP-based tool exposure"],"limitations":["TypeScript/JavaScript only — no native Python, Go, or Rust implementations in this package","Requires explicit transport configuration — no auto-detection of optimal transport","Message size limits depend on underlying transport (stdio has practical ~1MB limits)","No built-in request timeout enforcement — applications must implement their own timeout logic"],"requires":["Node.js 16.0.0 or higher","TypeScript 4.5+ (for type definitions)","@modelcontextprotocol/sdk package installed via npm","Understanding of JSON-RPC 2.0 protocol basics"],"input_types":["JSON-RPC 2.0 request objects","MCP protocol messages (initialize, call_tool, read_resource, etc.)","Transport-specific payloads (stdio streams, HTTP bodies, SSE events)"],"output_types":["JSON-RPC 2.0 response objects","MCP protocol responses with tool results or resource contents","Error responses with MCP-compliant error codes"],"categories":["tool-use-integration","protocol-implementation"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_1","uri":"capability://tool.use.integration.mcp.client.connection.management","name":"mcp-client-connection-management","description":"Implements MCP client-side connection handling with automatic transport selection, connection lifecycle management (initialization, capability negotiation, reconnection), and request multiplexing over a single bidirectional channel. 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Maintains request-response correlation and error handling for bidirectional communication.","intents":["I want my MCP server to ask the client for information or user input","I need to implement sampling or feedback loops where the server requests data from the client","I want to create interactive MCP workflows where servers and clients exchange requests"],"best_for":["Developers building interactive MCP workflows with bidirectional communication","Teams implementing sampling or feedback mechanisms in MCP servers","Applications that need servers to request information from clients"],"limitations":["Callback-based API can lead to callback hell in complex scenarios with many request types","No built-in request routing — all server-initiated requests go through registered callbacks","Timeout handling for server-initiated requests requires manual implementation","Error handling in callbacks can be tricky — exceptions may not propagate properly to the server"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Callback functions for handling server-initiated requests","Understanding of bidirectional communication patterns"],"input_types":["Server-initiated request messages with parameters","Request type identifiers"],"output_types":["Client responses to server requests","Error responses for failed request handling"],"categories":["tool-use-integration","automation-workflow"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_11","uri":"capability://tool.use.integration.capability.negotiation.and.versioning","name":"capability-negotiation-and-versioning","description":"Implements MCP protocol capability negotiation during server initialization where clients and servers exchange supported features, protocol versions, and implementation details. 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Tools are registered in a central registry that handles schema validation, type coercion, and parameter marshaling before passing arguments to tool handler functions. Supports nested object parameters, arrays, enums, and conditional schema validation.","intents":["I want to define tools with strict parameter validation without writing custom validation code","I need to expose my TypeScript functions as MCP tools with automatic schema generation","I want clients to discover what parameters my tools accept and what they return"],"best_for":["TypeScript developers building MCP servers with type-safe tool definitions","Teams standardizing tool interfaces across multiple services","Developers who want schema-driven tool discovery and validation"],"limitations":["Schema generation from TypeScript types requires explicit type annotations — inferred types may not generate accurate schemas","Complex union types and discriminated unions have limited schema representation","No built-in OpenAPI/Swagger generation — schemas are MCP-specific JSON Schema format","Runtime validation adds ~5-15ms overhead per tool call for complex schemas"],"requires":["TypeScript 4.5+ with strict mode enabled","@modelcontextprotocol/sdk package","JSON Schema knowledge for custom schema definitions","Tool handler functions with matching parameter signatures"],"input_types":["TypeScript type definitions","JSON Schema objects","Tool handler function signatures"],"output_types":["Validated parameter objects matching handler function signatures","JSON Schema representations of tool parameters","Tool metadata for client discovery"],"categories":["tool-use-integration","code-generation-editing"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_3","uri":"capability://tool.use.integration.resource.exposure.and.uri.routing","name":"resource-exposure-and-uri-routing","description":"Implements a resource system where servers expose files, documents, or data through URI-based routing with content type negotiation and streaming support. Resources are registered with URI patterns and handler functions that return content on demand. Supports text and binary content types, with automatic MIME type detection and optional caching hints for client-side optimization.","intents":["I want to expose files or documents from my system to MCP clients without copying them","I need to serve dynamic content (database records, API responses) as MCP resources","I want clients to discover available resources and their content types"],"best_for":["Developers building knowledge bases or document servers for Claude","Teams exposing internal APIs as resource endpoints","Applications that need to share large files or streaming content with AI clients"],"limitations":["No built-in pagination — large resources must be handled entirely in memory or streamed manually","URI routing is pattern-based, not regex-based — complex routing logic requires custom handlers","No built-in caching — servers must implement their own cache invalidation strategies","Resource discovery returns only URI patterns, not actual resource listings"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Resource handler functions that return content synchronously or via Promise","Understanding of URI schemes and MIME types"],"input_types":["Resource URI strings","URI pattern definitions","Content type specifications"],"output_types":["Text content (UTF-8 encoded)","Binary content (base64 encoded for transmission)","Resource metadata (URI, content type, size hints)"],"categories":["tool-use-integration","memory-knowledge"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_4","uri":"capability://tool.use.integration.prompt.template.and.argument.system","name":"prompt-template-and-argument-system","description":"Implements a prompt system where servers expose reusable prompt templates with typed arguments that clients can discover and invoke. Prompts are registered with argument schemas, descriptions, and handler functions that generate prompt text dynamically. Supports argument validation and allows prompts to be composed or chained by clients.","intents":["I want to expose prompt templates that Claude can use to structure its reasoning","I need to provide domain-specific prompts with validated arguments to AI clients","I want clients to discover available prompts and their expected arguments"],"best_for":["Teams building specialized AI workflows with domain-specific prompts","Developers creating prompt libraries for reuse across multiple applications","Organizations standardizing prompt engineering across their AI infrastructure"],"limitations":["Prompts are text-based — no support for structured prompt formats or multi-modal prompts","No built-in prompt versioning — clients must handle version negotiation manually","Argument validation is schema-based only — no semantic validation of prompt content","No prompt composition or templating language — complex prompts require manual string building"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Prompt handler functions that return text strings","JSON Schema definitions for prompt arguments"],"input_types":["Prompt argument objects matching registered schemas","Prompt names or identifiers"],"output_types":["Generated prompt text strings","Prompt metadata (name, description, arguments)"],"categories":["tool-use-integration","text-generation-language"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_5","uri":"capability://tool.use.integration.stdio.transport.implementation","name":"stdio-transport-implementation","description":"Implements stdio-based transport for MCP using child process stdin/stdout streams with line-delimited JSON message framing. Handles process spawning, stream buffering, message parsing, and graceful shutdown. Supports both server mode (listening for client connections via spawned processes) and client mode (connecting to server processes).","intents":["I want to run MCP servers as local processes and communicate via stdio","I need to integrate MCP with CLI tools or existing command-line applications","I want zero-network overhead for local MCP communication"],"best_for":["Developers building local development tools and IDE integrations","Teams running MCP servers on the same machine as clients","Applications that need to spawn and manage MCP server processes"],"limitations":["Practical message size limit of ~1MB due to stdio buffering constraints","No built-in process management — requires manual handling of process lifecycle, signals, and cleanup","Line-delimited JSON framing means binary data must be base64 encoded, adding ~33% overhead","Debugging is difficult — stdio streams are consumed by protocol, making standard debugging tools ineffective"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Executable MCP server binary or script","Proper signal handling for process cleanup (SIGTERM, SIGINT)"],"input_types":["Child process object or command string","Line-delimited JSON messages"],"output_types":["Line-delimited JSON responses","Process exit codes and error streams"],"categories":["tool-use-integration","automation-workflow"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_6","uri":"capability://tool.use.integration.http.sse.transport.implementation","name":"http-sse-transport-implementation","description":"Implements HTTP and Server-Sent Events (SSE) transport for MCP with request-response correlation over HTTP POST for client-to-server messages and SSE streams for server-to-client messages. Handles HTTP connection pooling, automatic reconnection on SSE stream loss, and message ordering guarantees across multiple HTTP requests.","intents":["I want to expose MCP servers over HTTP for remote access","I need to integrate MCP with web applications or cloud deployments","I want to use MCP across network boundaries with standard HTTP infrastructure"],"best_for":["Developers deploying MCP servers to cloud platforms or containers","Teams building web-based AI applications with remote MCP backends","Organizations using HTTP proxies, load balancers, or CDNs for MCP traffic"],"limitations":["SSE streams are unidirectional — server-to-client messages only, requiring HTTP POST for client-to-server","No built-in authentication or TLS — requires external reverse proxy or middleware for security","SSE reconnection can cause message loss if server doesn't implement proper message queuing","HTTP overhead adds ~50-100ms latency per request compared to stdio transport","No built-in rate limiting or backpressure handling — high-frequency tool calls can overwhelm HTTP connections"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","HTTP server framework (Express, Fastify, etc.) for server-side deployment","HTTP client library for client-side connections (built-in fetch or axios)"],"input_types":["HTTP POST request bodies with JSON-RPC messages","SSE event streams with JSON payloads"],"output_types":["HTTP response bodies with JSON-RPC responses","SSE event streams with server-initiated messages"],"categories":["tool-use-integration","automation-workflow"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_7","uri":"capability://tool.use.integration.error.handling.and.protocol.compliance","name":"error-handling-and-protocol-compliance","description":"Implements MCP-compliant error handling with standardized error codes, error propagation through JSON-RPC error responses, and automatic error serialization. Handles protocol violations, invalid requests, tool execution failures, and resource access errors with appropriate error codes and messages. Provides error context preservation for debugging.","intents":["I want errors from my tools to be properly communicated to MCP clients","I need to distinguish between protocol errors, tool errors, and resource errors","I want clients to understand why a tool call or resource access failed"],"best_for":["Developers building robust MCP servers with proper error reporting","Teams debugging integration issues between MCP clients and servers","Applications that need to handle tool failures gracefully"],"limitations":["Error codes are limited to MCP specification — custom error codes require wrapping in error messages","Stack traces are not transmitted by default — debugging requires server-side logging","Error context is limited to error code and message — no structured error metadata","Client-side error handling depends on proper error code interpretation — no automatic retry logic"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Understanding of MCP error codes and JSON-RPC error format","Proper error handling in tool handler functions"],"input_types":["Exceptions thrown by tool handlers","Invalid MCP protocol messages","Resource access failures"],"output_types":["JSON-RPC error response objects with MCP error codes","Error messages with context information"],"categories":["tool-use-integration","safety-moderation"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_8","uri":"capability://code.generation.editing.type.safe.handler.registration","name":"type-safe-handler-registration","description":"Provides TypeScript-first handler registration with compile-time type checking for tool and resource handlers. Handlers are registered with explicit type signatures that are validated against their implementation, ensuring parameter types match schema definitions and return types are compatible with MCP response formats. Uses TypeScript generics and overloads for type inference.","intents":["I want TypeScript to catch handler signature mismatches at compile time","I need to ensure my tool handlers match their schema definitions","I want IDE autocomplete for handler parameters and return types"],"best_for":["TypeScript developers building MCP servers with strict type safety","Teams using TypeScript for end-to-end type safety across client and server","Developers who want IDE support for handler implementation"],"limitations":["Requires TypeScript 4.5+ — no support for JavaScript-only projects without type annotations","Complex generic types can cause slow TypeScript compilation","Type inference works best with explicit parameter types — implicit types may not generate accurate schemas","Runtime validation still required — TypeScript types are erased at runtime"],"requires":["TypeScript 4.5+ with strict mode enabled","@modelcontextprotocol/sdk package","tsconfig.json with appropriate compiler options","IDE with TypeScript language server support (VS Code, WebStorm, etc.)"],"input_types":["TypeScript function signatures","Handler implementation functions"],"output_types":["Type-checked handler registrations","Compile-time type errors for mismatches"],"categories":["code-generation-editing","tool-use-integration"],"confidence":0.5,"matches":0,"success_rate":0},{"id":"npm_npm-modelcontextprotocolsdk__cap_9","uri":"capability://tool.use.integration.concurrent.request.multiplexing","name":"concurrent-request-multiplexing","description":"Implements request multiplexing over a single bidirectional MCP connection using JSON-RPC message IDs for request-response correlation. Handles concurrent tool calls, resource reads, and prompt invocations without blocking, using Promise-based async/await patterns and a message ID registry for tracking in-flight requests. Supports request cancellation and timeout handling.","intents":["I want to make multiple tool calls concurrently without opening separate connections","I need to handle responses arriving out of order from a single MCP connection","I want to cancel in-flight requests or implement request timeouts"],"best_for":["Developers building high-throughput MCP clients and servers","Applications making many concurrent tool calls to the same server","Teams optimizing network usage by multiplexing over single connections"],"limitations":["Message ID space is limited to 32-bit integers — extremely long-lived connections could theoretically wrap around","No built-in request prioritization — all requests are treated equally","Timeout handling is application-level — requires explicit timeout implementation per request","Request cancellation is not guaranteed — server may continue processing cancelled requests"],"requires":["Node.js 16.0.0 or higher","@modelcontextprotocol/sdk package","Understanding of Promise-based concurrency patterns","Proper error handling for concurrent request failures"],"input_types":["Multiple concurrent tool call requests","Resource read requests","Prompt invocation requests"],"output_types":["Responses correlated to original requests via message IDs","Error responses for failed requests"],"categories":["tool-use-integration","automation-workflow"],"confidence":0.5,"matches":0,"success_rate":0}],"trust":{"score":27,"verified":false,"data_access_risk":"moderate","permissions":["Node.js 16.0.0 or higher","TypeScript 4.5+ (for type definitions)","@modelcontextprotocol/sdk package installed via npm","Understanding of JSON-RPC 2.0 protocol basics","@modelcontextprotocol/sdk package","Access to at least one MCP server endpoint (stdio process, HTTP URL, or SSE endpoint)","Understanding of async/await and Promise-based error handling","Callback functions for handling server-initiated requests","Understanding of bidirectional communication patterns","Understanding of MCP protocol versions and capabilities"],"failure_modes":["TypeScript/JavaScript only — no native Python, Go, or Rust implementations in this package","Requires explicit transport configuration — no auto-detection of optimal transport","Message size limits depend on underlying transport (stdio has practical ~1MB limits)","No built-in request timeout enforcement — applications must implement their own timeout logic","Single connection per client instance — requires multiple instances for parallel server connections","No built-in connection pooling or load balancing across multiple server instances","Reconnection logic is basic exponential backoff — no sophisticated circuit breaker patterns","Callback-based server-initiated request handling can lead to callback hell in complex scenarios","Callback-based API can lead to callback hell in complex scenarios with many request types","No built-in request routing — all server-initiated requests go through registered callbacks","builder identity is not verified yet","no observed match outcomes yet"],"rank_breakdown":{"adoption":0.05,"quality":0.34,"ecosystem":0.36,"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":"2026-05-24T12:16:23.904Z","last_scraped_at":"2026-05-03T14:23:40.520Z","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=npm-modelcontextprotocolsdk","compare_url":"https://unfragile.ai/compare?artifact=npm-modelcontextprotocolsdk"}},"signature":"/H1iLFArxF6DH5Jj2jX6JLJqRfsJvCj11bR9z5S59TfPxV6Ljv7IqStj+4QwHa8oD0+jQeop5KIcZlSDzZi9CQ==","signedAt":"2026-06-21T04:51:08.768Z","signedBy":"unfragile.ai","version":1},"_links":{"self":"https://unfragile.ai/api/v1/passport/npm-modelcontextprotocolsdk","artifact":"https://unfragile.ai/npm-modelcontextprotocolsdk","verify":"https://unfragile.ai/api/v1/verify?slug=npm-modelcontextprotocolsdk","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"}}