{"id":4279,"date":"2026-01-15T16:31:46","date_gmt":"2026-01-15T22:31:46","guid":{"rendered":"https:\/\/ykim.synology.me\/wordpress\/?p=4279"},"modified":"2026-02-02T18:42:20","modified_gmt":"2026-02-03T00:42:20","slug":"what-is-model-context-protocol-mcp","status":"publish","type":"post","link":"https:\/\/ykim.synology.me\/wordpress\/what-is-model-context-protocol-mcp-4279\/","title":{"rendered":"Model Context Protocol (MCP)"},"content":{"rendered":"\n

[Gemini]<\/p>\n\n\n\n

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What is Model Context Protocol (MCP)?<\/h1>\n\n\n\n

The Model Context Protocol (MCP)<\/strong> is an open-source standard designed to enable seamless, secure communication between AI applications (hosts) and external data sources or tools (servers) [1, 4]. Introduced by Anthropic in late 2024 and adopted by major industry players like OpenAI and Google by 2025<\/strong>, MCP serves as a “universal adapter” that eliminates the need for developers to write custom integration code for every new AI model or service [5, 12].<\/p>\n\n\n\n

Core Architecture<\/h3>\n\n\n\n

MCP follows a modular client-server-host architecture inspired by the Language Server Protocol (LSP) [6, 9]:<\/p>\n\n\n\n

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  • MCP Host:<\/strong> The main AI application that contains the Large Language Model (LLM), such as Claude Desktop or an IDE like Cursor [2, 8].<\/li>\n\n\n\n
  • MCP Client:<\/strong> A lightweight component inside the host that maintains a dedicated connection to a server and handles the protocol’s translation [2, 9].<\/li>\n\n\n\n
  • MCP Server:<\/strong> An independent process that exposes specific capabilities like database access, web search, or file system operations [2, 7].<\/li>\n\n\n\n
  • Transport Layer:<\/strong> Standardizes message delivery using JSON-RPC 2.0<\/strong>. It typically uses stdio<\/strong> for local connections and Server-Sent Events (SSE)<\/strong> over HTTP for remote integrations [2, 10].<\/li>\n<\/ul>\n\n\n\n

    Key Primitives and 2026 Updates<\/h3>\n\n\n\n

    The protocol defines three core ways for servers to interact with the AI [2, 11]:<\/p>\n\n\n\n

    Primitive<\/strong><\/td>Function<\/strong><\/td>Example<\/strong><\/td><\/tr><\/thead>
    Tools<\/strong><\/td>Executable functions (verbs) the model can call.<\/td>query_db()<\/code>, send_email()<\/code><\/td><\/tr>
    Resources<\/strong><\/td>Read-only data sources (nouns) for context.<\/td>Database records, local files, logs<\/td><\/tr>
    Prompts<\/strong><\/td>Reusable templates for consistent patterns.<\/td>“Summarize this file,” “Code Review”<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    2026 Update (Sampling):<\/strong> The protocol now supports “Sampling,” which enables bidirectional communication. While servers were previously passive, they can now request completions from the host LLM to perform complex tasks, such as asking the model to verify if a code pattern is secure before the server executes a file scan [2, 8].<\/p>\n\n\n\n

    Strategic Benefits<\/h3>\n\n\n\n
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    • Reduced Hallucinations:<\/strong> By providing real-time access to authoritative data, models can verify information rather than relying on outdated training sets [1, 7].<\/li>\n\n\n\n
    • Enterprise Security:<\/strong> Sensitive credentials (like API keys) stay inside the server. The model only receives the specific data requested, and organizations can enforce fine-grained permissions at the session level [3, 12].<\/li>\n\n\n\n
    • Efficiency:<\/strong> Advanced “Code Mode” or on-demand loading reduces token consumption by up to 98% because the agent only processes tool definitions when they are relevant to the task [12].<\/li>\n<\/ul>\n\n\n\n

      Reference List<\/h3>\n\n\n\n
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      1. PythonAlchemist, “MCP Protocol Guide (2026): Build AI-Powered Agent Tools,” January 2026.<\/li>\n\n\n\n
      2. PythonAlchemist, “Sampling: Bidirectional AI Communication (2026 Update),” January 2026.<\/li>\n\n\n\n
      3. CData Software, “2026: The Year for Enterprise-Ready MCP Adoption,” December 2025.<\/li>\n\n\n\n
      4. ModelContextProtocol.io, “What is the Model Context Protocol (MCP)?,” 2026.<\/li>\n\n\n\n
      5. Wikipedia, “Model Context Protocol Industry Adoption and History,” 2026.<\/li>\n\n\n\n
      6. Descope, “What Is the Model Context Protocol (MCP) and How It Works,” September 2025.<\/li>\n\n\n\n
      7. Google Cloud, “What is Model Context Protocol (MCP)? A guide,” 2026.<\/li>\n\n\n\n
      8. ModelContextProtocol.io, “Architecture overview – Model Context Protocol,” 2026.<\/li>\n\n\n\n
      9. Nebius, “Understanding the Model Context Protocol (MCP): Architecture,” 2026.<\/li>\n\n\n\n
      10. Kubiya.ai, “Model Context Protocol (MCP): Architecture, Components & Workflow,” November 2025.<\/li>\n\n\n\n
      11. Medium, “MCP 201: Advanced Developer Use Cases for the Model Context Protocol,” January 2026.<\/li>\n\n\n\n
      12. Anthropic, “Code execution with MCP: building more efficient AI agents,” November 2025.<\/li>\n<\/ol>\n\n\n\n
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