{"id":"modelcontextprotocol-mcpb","name":"mcpb","homepage":null,"repo_url":"https://github.com/modelcontextprotocol/mcpb","category":"devtools","subcategories":[],"tags":["mcp","local-first","desktop","bundles","cli","manifest","automation","typescript","nodejs"],"what_it_does":"MCP Bundles (MCPB) is a TypeScript/Node.js toolchain and bundle format for packaging a local MCP server into a single .mcpb (zip) archive with a manifest.json describing server entrypoints and capabilities. It includes a CLI (mcpb init/pack) and reference code used by Claude for macOS/Windows to load, verify, and provide single-click installation with related end-user features like updates and configuration.","use_cases":["Distributing local MCP servers to end users in a portable, app-friendly way","Enabling desktop apps (e.g., Claude on macOS/Windows) to install local MCP servers via a standard bundle format","Creating and validating .mcpb archives from local MCP server source trees","Declaring MCP server capabilities and runtime requirements through manifest.json for host apps to configure/install"],"not_for":["Running server-side web APIs as a hosted SaaS","Remote multi-tenant access control for third-party users (the focus is local MCP servers)","Replacing the MCP protocol itself; it is a packaging/installation layer rather than an MCP transport or registry"],"best_when":"You want to ship a local MCP server to desktop users and have host apps implement MCPB bundle installation and configuration.","avoid_when":"You need a hosted, network-accessible service with server-side authentication, rate limiting, and SLAs; MCPB primarily targets local execution and distribution format interoperability.","alternatives":["Publishing the MCP server as an installer/package managed by the OS or app","Distributing source and having users run setup scripts","Using an existing MCP server registry/discovery mechanism if available in your target host ecosystem","Ad-hoc zip distribution with app-specific install logic (non-standard)"],"af_score":50.0,"security_score":20.2,"reliability_score":38.8,"package_type":"mcp_server","discovery_source":["github"],"priority":"high","status":"evaluated","version_evaluated":null,"last_evaluated":"2026-03-30T13:23:16.536050+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":[],"oauth":false,"scopes":false,"notes":"No API/service authentication is described; this is a local packaging tool and a bundle specification intended for local MCP servers loaded by desktop hosts."},"pricing":{"model":null,"free_tier_exists":false,"free_tier_limits":null,"paid_tiers":[],"requires_credit_card":false,"estimated_workload_costs":null,"notes":"Open-source package (Apache-2.0 / MIT as described). No pricing info for a hosted service."},"requirements":{"requires_signup":false,"requires_credit_card":false,"domain_verification":false,"data_residency":[],"compliance":[],"min_contract":null},"agent_readiness":{"af_score":50.0,"security_score":20.2,"reliability_score":38.8,"mcp_server_quality":30.0,"documentation_accuracy":75.0,"error_message_quality":0.0,"error_message_notes":null,"auth_complexity":95.0,"rate_limit_clarity":0.0,"tls_enforcement":0.0,"auth_strength":0.0,"scope_granularity":0.0,"dependency_hygiene":55.0,"secret_handling":60.0,"security_notes":"Security is primarily about packaging/manifest integrity and safe local execution; the provided material does not describe TLS, auth, or scope controls because this is not a network API. Dependency hygiene is unknown beyond the listed runtime dependencies. Bundling all server files (including node_modules) increases supply-chain risk; users/hosts should validate signatures/hashes if supported and avoid executing untrusted bundles.","uptime_documented":0.0,"version_stability":70.0,"breaking_changes_history":50.0,"error_recovery":35.0,"idempotency_support":"false","idempotency_notes":null,"pagination_style":"none","retry_guidance_documented":false,"known_agent_gotchas":["mcpb bundles are zip archives; incorrect manifest.json fields or mismatched server.entry_point/runtime.type may cause host verification/install failures","Host apps (e.g., Claude for macOS/Windows) implement installation/verification logic; behavior and constraints may differ across hosts and bundle types","Packaging entire node_modules into a bundle can increase size and may cause unexpected runtime issues on the host if dependencies or binaries are incompatible with the platform"]}}