{"id":"langchain-ai-langchainjs-mcp-adapters","name":"langchainjs-mcp-adapters","homepage":null,"repo_url":"https://github.com/langchain-ai/langchainjs-mcp-adapters","category":"devtools","subcategories":[],"tags":["langchain","langchainjs","mcp","model-context-protocol","typescript","agent-tools","ai-tools","sse","stdio"],"what_it_does":"Provides LangChain.js adapters to integrate Model Context Protocol (MCP) tools into LangChain.js applications, supporting MCP tool usage over stdio and SSE transports via the @modelcontextprotocol/sdk dependency.","use_cases":["Use MCP tool servers from within LangChain.js agent workflows","Bridge existing MCP tool ecosystems into LangChain.js tool calling","Run MCP tools over stdio or SSE in a Node.js/TypeScript LangChain application"],"not_for":["Directly exposing a public REST/GraphQL/gRPC API to end users","Handling authentication/authorization for your MCP tools server (this adapter is a client-side wrapper)","Implementing large-scale tool orchestration without considering MCP server availability and transport behavior"],"best_when":"You want to connect LangChain.js agents to MCP tool servers and you already operate (or can operate) an MCP server using stdio or SSE transports.","avoid_when":"You need a turnkey hosted service with built-in auth, billing, and operational guarantees instead of a library adapter.","alternatives":["Use @modelcontextprotocol/sdk directly with custom LangChain.js tool wrappers","LangChain.js monorepo’s moved-in libs/langchain-mcp-adapters implementation","Other MCP-to-framework adapters if available for your stack"],"af_score":39.5,"security_score":46.0,"reliability_score":32.5,"package_type":"mcp_server","discovery_source":["github"],"priority":"high","status":"evaluated","version_evaluated":null,"last_evaluated":"2026-03-30T13:35:48.018304+00:00","interface":{"has_rest_api":false,"has_graphql":false,"has_grpc":false,"has_mcp_server":false,"mcp_server_url":null,"has_sdk":true,"sdk_languages":["TypeScript","JavaScript"],"openapi_spec_url":null,"webhooks":false},"auth":{"methods":["Depends on MCP transport/server configuration (not evidenced in provided README/manifest)"],"oauth":false,"scopes":false,"notes":"No authentication mechanism is described in the provided README/manifest; any auth is likely handled by the MCP server/transport layer outside this wrapper."},"pricing":{"model":null,"free_tier_exists":false,"free_tier_limits":null,"paid_tiers":[],"requires_credit_card":false,"estimated_workload_costs":null,"notes":"Open-source npm package (MIT) per repository metadata; costs are operational (running MCP servers/LLMs) rather than subscription by this package."},"requirements":{"requires_signup":false,"requires_credit_card":false,"domain_verification":false,"data_residency":[],"compliance":[],"min_contract":null},"agent_readiness":{"af_score":39.5,"security_score":46.0,"reliability_score":32.5,"mcp_server_quality":55.0,"documentation_accuracy":35.0,"error_message_quality":0.0,"error_message_notes":null,"auth_complexity":90.0,"rate_limit_clarity":0.0,"tls_enforcement":60.0,"auth_strength":30.0,"scope_granularity":20.0,"dependency_hygiene":70.0,"secret_handling":60.0,"security_notes":"As a client-side adapter/library, it likely inherits transport security and auth behavior from the MCP server and @modelcontextprotocol/sdk. The provided materials do not mention auth, secrets handling, or TLS requirements directly.","uptime_documented":0.0,"version_stability":60.0,"breaking_changes_history":40.0,"error_recovery":30.0,"idempotency_support":"false","idempotency_notes":"No idempotency guarantees are described in the provided README/manifest; idempotency depends on underlying MCP tool implementations.","pagination_style":"none","retry_guidance_documented":false,"known_agent_gotchas":["Adapter migration: repository indicates the package moved into the LangChainJS monorepo; consumers may need to update import paths/version alignment.","Transport-specific behavior: stdio vs SSE can affect lifecycle and error/reconnect semantics; agent retry strategies may vary accordingly.","This adapter likely does not enforce tool-level auth/authorization; misconfigured MCP server permissions could surface as tool call failures."]}}