Model Context Protocol (MCP)

name: Model Context Protocol (MCP)
description: Model Context Protocol is an open, JSON-RPC 2.0 protocol from Anthropic that standardizes how AI applications
  (hosts) connect to external systems via servers that expose tools, resources, and prompts. MCP is positioned as "a USB-C
  port for AI applications" and has become the de-facto integration layer for Claude, ChatGPT, Cursor, Visual Studio Code,
  and a growing ecosystem of agent runtimes. This topic repo catalogs the canonical specification, the official multi-language
  SDKs, the reference server collection, community registries (Smithery, Pulse MCP, Naftiko Sandbox), and major MCP-aware
  clients, plus the vocabulary, JSON Schema, JSON-LD, and example payloads needed to reason about the protocol.
url: https://github.com/api-evangelist/mcp
humanURL: https://modelcontextprotocol.io
image: ''
tags:
- Model Context Protocol
- MCP
- AI Agents
- Tools
- Resources
- Prompts
- JSON-RPC
- Anthropic
- Standards
- Topic
created: '2026-05-22'
modified: '2026-05-22'
specificationVersion: '0.18'
type: Index
apis:
- name: MCP Specification
  description: The authoritative protocol definition for the Model Context Protocol, maintained at modelcontextprotocol.io
    and in the modelcontextprotocol/ specification GitHub repository. The TypeScript schema (schema.ts) is the source of truth,
    with an auto-generated JSON Schema (schema.json) for tooling. The current dated version is 2025-11-25. The protocol uses
    JSON-RPC 2.0 messages between hosts, clients, and servers and defines tools, resources, prompts, sampling, roots, elicitation,
    completion, and logging features.
  humanURL: https://modelcontextprotocol.io/specification
  baseURL: ''
  tags:
  - Specification
  - JSON-RPC
  - Schema
  - Protocol
  properties:
  - type: Documentation
    url: https://modelcontextprotocol.io/specification/2025-11-25
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/specification
  - type: JSONSchema
    url: https://github.com/modelcontextprotocol/specification/blob/main/schema/2025-11-25/schema.json
  - type: Versioning
    url: https://modelcontextprotocol.io/specification/versioning
- name: MCP TypeScript SDK
  description: Official TypeScript SDK published as @modelcontextprotocol/sdk on npm. Dual-purpose library for building MCP
    servers and clients on Node.js, Bun, and Deno. Supports Standard Schema (Zod, Valibot, ArkType), stdio and Streamable
    HTTP transports, and ships thin middleware adapters for Express, Hono, and Node HTTP. The v2 line is in development.
  humanURL: https://github.com/modelcontextprotocol/typescript-sdk
  tags:
  - SDK
  - TypeScript
  - Node.js
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/typescript-sdk
  - type: SDKs
    url: https://www.npmjs.com/package/@modelcontextprotocol/sdk
- name: MCP Python SDK
  description: Official Python SDK published as `mcp` on PyPI. Includes the FastMCP high-level framework with decorators for
    tools, resources, and prompts; low-level server primitives for production; client SDK; OAuth 2.1 resource-server support;
    and stdio, SSE, and Streamable HTTP transports. Structured output is validated through Pydantic.
  humanURL: https://github.com/modelcontextprotocol/python-sdk
  tags:
  - SDK
  - Python
  - FastMCP
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/python-sdk
  - type: SDKs
    url: https://pypi.org/project/mcp/
- name: MCP Java SDK
  description: Official Java SDK for building MCP servers and clients on the JVM. Maintained in the modelcontextprotocol/java-sdk
    repository.
  humanURL: https://github.com/modelcontextprotocol/java-sdk
  tags:
  - SDK
  - Java
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/java-sdk
- name: MCP Kotlin SDK
  description: Official Kotlin SDK for MCP servers and clients targeting Kotlin and Android runtimes.
  humanURL: https://github.com/modelcontextprotocol/kotlin-sdk
  tags:
  - SDK
  - Kotlin
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/kotlin-sdk
- name: MCP C# SDK
  description: Official C# SDK for .NET, maintained in collaboration with Microsoft.
  humanURL: https://github.com/modelcontextprotocol/csharp-sdk
  tags:
  - SDK
  - CSharp
  - .NET
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/csharp-sdk
- name: MCP Swift SDK
  description: Official Swift SDK for MCP servers and clients on Apple platforms.
  humanURL: https://github.com/modelcontextprotocol/swift-sdk
  tags:
  - SDK
  - Swift
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/swift-sdk
- name: MCP Rust SDK
  description: Official Rust SDK for MCP servers and clients.
  humanURL: https://github.com/modelcontextprotocol/rust-sdk
  tags:
  - SDK
  - Rust
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/rust-sdk
- name: MCP Reference Servers
  description: Canonical collection of reference MCP server implementations maintained by the project. The active servers
    (Everything, Fetch, Filesystem, Git, Memory, Sequential Thinking, Time) demonstrate every server-side feature of the protocol
    and are recommended as the starting point for new implementers.
  humanURL: https://github.com/modelcontextprotocol/servers
  tags:
  - Reference
  - Servers
  - Examples
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/servers
- name: MCP Inspector
  description: Developer tool for testing and debugging MCP servers. React-based web UI plus Node.js proxy, launched with
    `npx @modelcontextprotocol/inspector` and accessible at http://localhost:6274. Provides interactive testing of tools,
    resources, and prompts, plus a CLI mode for scripted testing.
  humanURL: https://github.com/modelcontextprotocol/inspector
  tags:
  - Tooling
  - Debugging
  - Inspector
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/inspector
  - type: CLI
    url: https://www.npmjs.com/package/@modelcontextprotocol/inspector
- name: Official MCP Registry
  description: Community-driven, Anthropic-maintained registry that functions as an app store for MCP servers. Allows developers
    to publish server definitions and clients to discover them. Currently in API freeze at v0.1. Supports GitHub OAuth, GitHub
    OIDC, and DNS/HTTP ownership verification.
  humanURL: https://registry.modelcontextprotocol.io
  baseURL: https://registry.modelcontextprotocol.io
  tags:
  - Registry
  - Discovery
  properties:
  - type: GitHubRepository
    url: https://github.com/modelcontextprotocol/registry
  - type: APIReference
    url: https://registry.modelcontextprotocol.io/docs
- name: Smithery
  description: Third-party MCP server registry and hosted runtime. Catalogs community-built MCP servers, generates installation
    snippets for clients like Claude Desktop and Cursor, and can host servers on Smithery's infrastructure. Acts as a primary
    discovery surface alongside the official registry.
  humanURL: https://smithery.ai
  tags:
  - Registry
  - Hosted
  - Discovery
  properties:
  - type: Portal
    url: https://smithery.ai
- name: Pulse MCP
  description: Third-party MCP directory and news site. Maintains a sub-registry API that implements the Generic MCP Registry
    API specification with PulseMCP-specific extensions for enriched metadata.
  humanURL: https://www.pulsemcp.com
  tags:
  - Registry
  - News
  - Discovery
  properties:
  - type: Portal
    url: https://www.pulsemcp.com
  - type: APIReference
    url: https://www.pulsemcp.com/api/docs/v0.1
- name: Claude Desktop (MCP Host)
  description: Anthropic's Claude Desktop application was the first MCP host. Connects to local MCP servers via stdio transport
    defined in claude_desktop_config .json and to remote servers via Streamable HTTP with OAuth 2.1.
  humanURL: https://claude.com/docs/connectors/building
  tags:
  - Client
  - Host
  - Claude
  properties:
  - type: Documentation
    url: https://claude.com/docs/connectors/building
- name: Cursor (MCP Host)
  description: Cursor IDE supports MCP servers as a first-class extension mechanism, configured via mcp.json. Cursor is one
    of the most widely used MCP hosts for code-related workflows.
  humanURL: https://cursor.com/docs/context/mcp
  tags:
  - Client
  - IDE
  - Cursor
  properties:
  - type: Documentation
    url: https://cursor.com/docs/context/mcp
- name: Visual Studio Code (MCP Host)
  description: VS Code's GitHub Copilot Chat integrates MCP servers as agents and tools. Microsoft has standardized on MCP
    for Copilot's agent-mode extensibility.
  humanURL: https://code.visualstudio.com/docs/copilot/chat/mcp-servers
  tags:
  - Client
  - IDE
  - VSCode
  properties:
  - type: Documentation
    url: https://code.visualstudio.com/docs/copilot/chat/mcp-servers
- name: ChatGPT (MCP Host)
  description: OpenAI's ChatGPT supports MCP through the Apps SDK and developer tooling documented at developers.openai.com,
    making MCP a cross-vendor surface for connecting tools and data to ChatGPT.
  humanURL: https://developers.openai.com/api/docs/mcp/
  tags:
  - Client
  - Host
  - OpenAI
  properties:
  - type: Documentation
    url: https://developers.openai.com/api/docs/mcp/
common:
- type: AgentCard
  url: a2a/mcp-a2a.yml
  name: A2A Agent Card
  description: Agent Card served at /.well-known/agent-card.json (near-conformant against A2A 1.0.0).
- type: VulnerabilityDisclosure
  url: security/mcp-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/mcp-domain-security.yml
- type: Blog
  url: https://blog.modelcontextprotocol.io/index.xml
- type: Portal
  url: https://modelcontextprotocol.io
- type: Documentation
  url: https://modelcontextprotocol.io/introduction
- type: GitHubOrganization
  url: https://github.com/modelcontextprotocol
- type: GitHubRepository
  url: https://github.com/modelcontextprotocol/specification
- type: Vocabulary
  url: vocabulary/mcp-vocabulary.yml
- type: JSONLD
  url: json-ld/mcp-context.jsonld
- type: Features
  data:
  - name: JSON-RPC 2.0 Base Protocol
    description: MCP defines request, response, and notification message shapes on top of JSON-RPC 2.0 with strict rules on
      IDs and structure.
  - name: Stateful Sessions
    description: Clients and servers negotiate capabilities during the initialize handshake and maintain stateful connections
      for the lifetime of the session.
  - name: Tools
    description: Servers expose callable tools with JSON Schema 2020-12 input schemas; clients invoke them via tools/call.
  - name: Resources
    description: Servers expose URI-addressable context (files, database rows, API responses) via resources/list, resources/read,
      and subscription notifications.
  - name: Prompts
    description: Servers expose templated prompts and workflows via prompts/list and prompts/get for users to invoke.
  - name: Sampling
    description: Clients can offer sampling/createMessage so servers can ask the host LLM to run agentic, recursive inference
      under user consent.
  - name: Roots
    description: Clients can advertise filesystem roots that bound a server's operating scope via roots/list.
  - name: Elicitation
    description: Servers can request additional information from users mid-session via elicitation/create.
  - name: Multiple Transports
    description: MCP defines stdio for local processes and Streamable HTTP (with an optional SSE legacy mode) for networked
      deployments.
  - name: OAuth 2.1 Authorization
    description: HTTP-based transports follow an MCP-defined OAuth 2.1 authorization framework; stdio transports retrieve
      credentials from the environment.
  - name: Icons and Branding
    description: Implementations, tools, prompts, and resources can publish icon metadata for richer UIs, with strict security
      constraints on icon URIs.
  - name: Reserved _meta Namespace
    description: MCP reserves the _meta property with a structured prefix/name format for attaching additional metadata to
      interactions.
- type: UseCases
  data:
  - name: IDE Augmentation
    description: MCP servers extend coding assistants like Cursor, VS Code Copilot, and Claude Code with project-aware tools,
      repository search, and terminal/build access.
  - name: Knowledge Base Access
    description: MCP resources surface documentation, wikis, and structured data stores to AI hosts under user consent.
  - name: Workflow Automation
    description: MCP tools let agents trigger build pipelines, send notifications, create tickets, and orchestrate multi-step
      business workflows.
  - name: Enterprise Connectors
    description: Vendors expose enterprise systems (CRMs, ITSM, data warehouses) as MCP servers so that any MCP-aware host
      can connect without bespoke integration code.
  - name: Local Computer Use
    description: Local MCP servers expose filesystem, git, shell, browser, and desktop automation tools to assistants running
      on the same machine.
- type: Integrations
  data:
  - name: Anthropic Claude
    description: Claude Desktop, Claude Code, and the Claude API are first-class MCP hosts and are the protocol's reference
      consumers.
  - name: OpenAI ChatGPT
    description: ChatGPT supports MCP through the Apps SDK and OpenAI's developer docs.
  - name: Cursor
    description: Cursor IDE consumes MCP servers via mcp.json configuration.
  - name: Visual Studio Code
    description: VS Code's Copilot Chat treats MCP servers as agents and tools.
  - name: MCPJam
    description: MCPJam is a community client implementation for testing MCP servers interactively.
- type: Solutions
  data:
  - name: Spec, SDKs, and Reference Servers
    description: modelcontextprotocol.io publishes the spec, schema, official SDKs for TypeScript, Python, Java, Kotlin, C#,
      Swift, and Rust, plus a set of reference servers and an Inspector debugging tool.
  - name: Official Registry
    description: The official MCP Registry is a central index of MCP servers with GitHub OAuth/OIDC and DNS-based ownership
      verification.
  - name: Third-Party Registries
    description: Smithery and Pulse MCP provide alternative discovery surfaces and, in Smithery's case, hosted execution of
      community servers.
  - name: Vendor Hosts
    description: Claude, ChatGPT, Cursor, VS Code Copilot, Continue, Cline, Zed, Windsurf, and many other assistants act as
      MCP hosts.
maintainers:
- FN: Kin Lane
  email: kinlane@gmail.com
  url: http://kinlane.com