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	<meta charset="utf-8" /><meta name="hf:doc:metadata" content="{"title":"MCP Key Concepts and Architecture","local":"mcp-key-concepts-and-architecture","sections":[{"title":"The Three Roles: Hosts, Clients, and Servers","local":"the-three-roles-hosts-clients-and-servers","sections":[{"title":"Host","local":"host","sections":[],"depth":3},{"title":"Client","local":"client","sections":[],"depth":3},{"title":"Server","local":"server","sections":[],"depth":3}],"depth":2},{"title":"The Three Capability Types","local":"the-three-capability-types","sections":[{"title":"Tools","local":"tools","sections":[],"depth":3},{"title":"Resources","local":"resources","sections":[],"depth":3},{"title":"Prompts","local":"prompts","sections":[],"depth":3}],"depth":2},{"title":"Communication Protocol: JSON-RPC Over Transports","local":"communication-protocol-json-rpc-over-transports","sections":[],"depth":2},{"title":"Transport Mechanisms","local":"transport-mechanisms","sections":[{"title":"Stdio Transport","local":"stdio-transport","sections":[],"depth":3},{"title":"Streamable HTTP Transport","local":"streamable-http-transport","sections":[],"depth":3}],"depth":2},{"title":"MCP Architecture Diagram","local":"mcp-architecture-diagram","sections":[],"depth":2},{"title":"Tools vs. Resources vs. Prompts: A Comparison","local":"tools-vs-resources-vs-prompts-a-comparison","sections":[],"depth":2},{"title":"The MCP Lifecycle","local":"the-mcp-lifecycle","sections":[],"depth":2},{"title":"Key Takeaways","local":"key-takeaways","sections":[],"depth":2}],"depth":1}">
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	<link rel="modulepreload" href="/docs/context-course/pr_7/en/_app/immutable/chunks/stores.0a12db33.js"><!-- HEAD_svelte-u9bgzb_START --><meta name="hf:doc:metadata" content="{"title":"MCP Key Concepts and Architecture","local":"mcp-key-concepts-and-architecture","sections":[{"title":"The Three Roles: Hosts, Clients, and Servers","local":"the-three-roles-hosts-clients-and-servers","sections":[{"title":"Host","local":"host","sections":[],"depth":3},{"title":"Client","local":"client","sections":[],"depth":3},{"title":"Server","local":"server","sections":[],"depth":3}],"depth":2},{"title":"The Three Capability Types","local":"the-three-capability-types","sections":[{"title":"Tools","local":"tools","sections":[],"depth":3},{"title":"Resources","local":"resources","sections":[],"depth":3},{"title":"Prompts","local":"prompts","sections":[],"depth":3}],"depth":2},{"title":"Communication Protocol: JSON-RPC Over Transports","local":"communication-protocol-json-rpc-over-transports","sections":[],"depth":2},{"title":"Transport Mechanisms","local":"transport-mechanisms","sections":[{"title":"Stdio Transport","local":"stdio-transport","sections":[],"depth":3},{"title":"Streamable HTTP Transport","local":"streamable-http-transport","sections":[],"depth":3}],"depth":2},{"title":"MCP Architecture Diagram","local":"mcp-architecture-diagram","sections":[],"depth":2},{"title":"Tools vs. Resources vs. Prompts: A Comparison","local":"tools-vs-resources-vs-prompts-a-comparison","sections":[],"depth":2},{"title":"The MCP Lifecycle","local":"the-mcp-lifecycle","sections":[],"depth":2},{"title":"Key Takeaways","local":"key-takeaways","sections":[],"depth":2}],"depth":1}"><!-- HEAD_svelte-u9bgzb_END --> <p></p> <div class="items-center shrink-0 min-w-[100px] max-sm:min-w-[50px] justify-end ml-auto flex" style="float: right; margin-left: 10px; display: inline-flex; position: relative; z-index: 10;"><div 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href="#mcp-key-concepts-and-architecture"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>MCP Key Concepts and Architecture</span></h1> <p data-svelte-h="svelte-1yvt87f">MCP has three roles — <strong>hosts</strong>, <strong>clients</strong>, and <strong>servers</strong> — that exchange three kinds of capability: <strong>tools</strong>, <strong>resources</strong>, and <strong>prompts</strong>.</p> <iframe src="https://context-course-mcp-handshake.static.hf.space" frameborder="0" width="850" height="450"></iframe> <h2 class="relative group"><a id="the-three-roles-hosts-clients-and-servers" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#the-three-roles-hosts-clients-and-servers"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>The Three Roles: Hosts, Clients, and Servers</span></h2> <p data-svelte-h="svelte-18il5hq">Every MCP interaction involves three distinct roles:</p> <h3 class="relative group"><a id="host" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#host"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Host</span></h3> <p data-svelte-h="svelte-nc9b4t">The <strong>host</strong> is the environment where a code agent runs. Examples:</p> <ul data-svelte-h="svelte-cvtgq4"><li>Claude Code (CLI tool)</li> <li>Codex (OpenAI’s code agent)</li> <li>OpenCode (open source agent)</li> <li>A custom Python script using an AI SDK</li></ul> <p data-svelte-h="svelte-149b6v1">The host manages the MCP client connection and presents results to the user. The host doesn’t implement MCP itself—it delegates protocol handling to the client.</p> <h3 class="relative group"><a id="client" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#client"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Client</span></h3> <p data-svelte-h="svelte-tmksdj">The <strong>client</strong> is the protocol handler inside the host that communicates with MCP servers. It:</p> <ul data-svelte-h="svelte-cu0mu5"><li>Discovers available servers and their capabilities</li> <li>Sends requests to servers (call tools, read resources, retrieve prompts)</li> <li>Handles responses and errors</li> <li>Maintains the connection lifecycle</li> <li>Manages authentication if needed</li></ul> <p data-svelte-h="svelte-1o9hdgx">In practice, the client is built into the agent’s runtime (like Claude Code’s built-in MCP support or Codex’s MCP client).</p> <h3 class="relative group"><a id="server" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#server"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Server</span></h3> <p data-svelte-h="svelte-1wl2wr">The <strong>server</strong> is an external program that exposes capabilities through MCP. It:</p> <ul data-svelte-h="svelte-uyxt2j"><li>Defines what tools it provides (with schemas and descriptions)</li> <li>Exposes what resources are available (with URIs and content)</li> <li>Implements prompts (instruction templates)</li> <li>Handles incoming requests from clients</li> <li>Returns results in the MCP protocol format</li></ul> <p data-svelte-h="svelte-gows6f">A server can be:</p> <ul data-svelte-h="svelte-hr87i"><li>A Python script on your laptop</li> <li>A deployed service on Hugging Face Spaces</li> <li>A containerized application</li> <li>Embedded in your application (like a Gradio app with <code>mcp_server=True</code>)</li></ul> <h2 class="relative group"><a id="the-three-capability-types" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#the-three-capability-types"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>The Three Capability Types</span></h2> <p data-svelte-h="svelte-117w989">MCP servers expose three kinds of capabilities to clients:</p> <h3 class="relative group"><a id="tools" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#tools"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Tools</span></h3> <p data-svelte-h="svelte-12nqn2g">Tools are callable functions that agents invoke to perform actions or retrieve data. Each tool has a unique name (like <code>search_github</code>), a description of what it does, a JSON Schema defining its input parameters, and the actual function implementation. When an agent reasons that a tool would help with the current task, it calls the tool with appropriate parameters, the server executes it and returns results, and the agent incorporates those results into its reasoning. Tools are model-controlled — the agent decides whether and when to call them. They can modify state (writing files, sending messages), include error handling, and return structured or unstructured results.</p> <h3 class="relative group"><a id="resources" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#resources"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Resources</span></h3> <p data-svelte-h="svelte-z439nd">Resources are read-only data sources that agents can access for information. Each resource has a URI (like <code>file:///path/to/code.py</code>), a human-readable name, a description, and a MIME type. When an agent needs information to reason about a problem, it requests a resource by URI, the server retrieves the content, and the agent uses it as context. Unlike tools, resources are application-controlled — the host determines what is exposed. They’re always available without being explicitly called, making them ideal for static or semi-static data like project files, documentation, or configuration.</p> <h3 class="relative group"><a id="prompts" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#prompts"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Prompts</span></h3> <p data-svelte-h="svelte-174nyqt">Prompts are instruction templates that agents can request to help guide their own behavior for specific contexts or domains. Each prompt has a name (like <code>code_review</code>), a description of when it applies, optional arguments for dynamic behavior, and the actual template text. When an agent recognizes a situation where a prompt applies, it requests the prompt (optionally with arguments), receives the instantiated text, and uses it to structure its reasoning. Prompts are user-controlled — they’re deployed separately and updated independently. They’re non-executable text instructions, ideal for standardizing approaches to recurring tasks like code reviews or security audits.</p> <blockquote class="note" data-svelte-h="svelte-ejpsj1"><p>On average, about ~90% of MCP usage is for tools.</p></blockquote> <h2 class="relative group"><a id="communication-protocol-json-rpc-over-transports" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#communication-protocol-json-rpc-over-transports"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Communication Protocol: JSON-RPC Over Transports</span></h2> <p data-svelte-h="svelte-icps8x">MCP uses <strong>JSON-RPC 2.0</strong> as its messaging protocol. Every request and response is a JSON-RPC message. The protocol is transport-agnostic—the same JSON-RPC format works over any transport.</p> <blockquote class="note" data-svelte-h="svelte-p6k0hl"><p>A transport can be defined as any communication channel that carries a message. For example, processes that exist on the same machine (stdio), or connect over a network connection (e.g. HTTP).</p></blockquote> <p data-svelte-h="svelte-rwf0id">A typical client request to call a tool:</p> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"jsonrpc"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"2.0"</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"id"</span><span class="hljs-punctuation">:</span> <span class="hljs-number">1</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"method"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"tools/call"</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"params"</span><span class="hljs-punctuation">:</span> <span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"name"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"search_github"</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"arguments"</span><span class="hljs-punctuation">:</span> <span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"query"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"code agents"</span>
	<span class="hljs-punctuation">}</span>
	<span class="hljs-punctuation">}</span>
	<span class="hljs-punctuation">}</span><!-- HTML_TAG_END --></pre></div> <p data-svelte-h="svelte-lzvy0q">The server responds:</p> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"jsonrpc"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"2.0"</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"id"</span><span class="hljs-punctuation">:</span> <span class="hljs-number">1</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"result"</span><span class="hljs-punctuation">:</span> <span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"content"</span><span class="hljs-punctuation">:</span> <span class="hljs-punctuation">[</span>
	<span class="hljs-punctuation">{</span>
	<span class="hljs-attr">"type"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"text"</span><span class="hljs-punctuation">,</span>
	<span class="hljs-attr">"text"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"[GitHub search results...]"</span>
	<span class="hljs-punctuation">}</span>
	<span class="hljs-punctuation">]</span>
	<span class="hljs-punctuation">}</span>
	<span class="hljs-punctuation">}</span><!-- HTML_TAG_END --></pre></div> <p data-svelte-h="svelte-19nzo23">MCP defines specific methods like <code>tools/list</code>, <code>tools/call</code>, <code>resources/list</code>, <code>resources/read</code>, and <code>prompts/get</code>.</p> <h2 class="relative group"><a id="transport-mechanisms" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#transport-mechanisms"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Transport Mechanisms</span></h2> <p data-svelte-h="svelte-1iolh1z">The protocol (JSON-RPC) is separate from the transport (how messages move between client and server). MCP defines two standard transports.</p> <h3 class="relative group"><a id="stdio-transport" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#stdio-transport"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Stdio Transport</span></h3> <p data-svelte-h="svelte-yee5oc">For <strong>local connections</strong> where the server runs on your machine:</p> <ul data-svelte-h="svelte-99tmr"><li>Server runs as a subprocess of the host</li> <li>Communication happens via stdin/stdout</li> <li>No network overhead</li> <li>Perfect for development and local tools</li> <li>Most secure (no network exposure)</li></ul> <p data-svelte-h="svelte-q59zuc">Configuration:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white">Claude Code </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">Codex </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">OpenCode </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">Pi </div></div> <div class="language-select"><div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->claude mcp add --transport stdio my-server -- python /path/to/server.py<!-- HTML_TAG_END --></pre></div> </div> <h3 class="relative group"><a id="streamable-http-transport" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#streamable-http-transport"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Streamable HTTP Transport</span></h3> <p data-svelte-h="svelte-fjecc2">For <strong>remote connections</strong> where the server runs elsewhere:</p> <ul data-svelte-h="svelte-1amzdjm"><li>Client makes HTTP POST requests to a single endpoint</li> <li>Server responds with JSON-RPC results or SSE streams</li> <li>Works across the internet and through firewalls</li> <li>Ideal for cloud deployments and shared resources</li> <li>Supports authentication headers and session management</li></ul> <p data-svelte-h="svelte-3k8348">Streamable HTTP is the current standard for remote MCP servers, introduced in protocol revision 2025-03-26 and carried forward in subsequent revisions. The older HTTP+SSE transport from 2024-11-05 is deprecated but still supported for backward compatibility.</p> <p data-svelte-h="svelte-q59zuc">Configuration:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white">Claude Code </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">Codex </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">OpenCode </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">Pi </div></div> <div class="language-select"><div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->claude mcp add hf-mcp-server -t http <span class="hljs-string">"https://huggingface.co/mcp?login"</span><!-- HTML_TAG_END --></pre></div> </div> <table data-svelte-h="svelte-zssjke"><thead><tr><th>Aspect</th> <th>Stdio</th> <th>Streamable HTTP</th></tr></thead> <tbody><tr><td><strong>Location</strong></td> <td>Local</td> <td>Remote</td></tr> <tr><td><strong>Network</strong></td> <td>None</td> <td>Internet</td></tr> <tr><td><strong>Setup</strong></td> <td>Simple</td> <td>Simple</td></tr> <tr><td><strong>Performance</strong></td> <td>Very fast</td> <td>Network latency</td></tr> <tr><td><strong>Security</strong></td> <td>No exposure</td> <td>Requires auth</td></tr> <tr><td><strong>Use Case</strong></td> <td>Development, single user</td> <td>Production, teams, cloud</td></tr></tbody></table> <h2 class="relative group"><a id="mcp-architecture-diagram" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#mcp-architecture-diagram"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>MCP Architecture Diagram</span></h2> <p data-svelte-h="svelte-6l7572">Here’s how it all fits together:</p> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->┌─────────────────────────────────────────┐
	│ Code Agent (Host) │
	│ (Claude Code, Codex, OpenCode) │
	└──────────┬──────────────────────────────┘
	│
	│ MCP Client
	│ <span class="hljs-type">JSON</span>-RPC messages
	│
	┌──────┴─────────┬──────────────┬──────────────┐
	│ │ │ │
	▼ ▼ ▼ ▼
	┌────────────┐ ┌────────────┐ ┌────────────┐ ┌────────────┐
	│ GitHub │ │ Slack │ │ <span class="hljs-type">Internal</span> │ │ Project │
	│ MCP <span class="hljs-keyword">Server</span> │ │ MCP <span class="hljs-keyword">Server</span> │ │ API <span class="hljs-keyword">Server</span> │ │ MCP <span class="hljs-keyword">Server</span> │
	│ │ │ │ │ │ │ │
	│ Tools: │ │ Tools: │ │ Tools: │ │ Resources: │
	│ -list_prs │ │ -send_msg │ │ -query_db │ │ -code.py │
	│ -<span class="hljs-keyword">search</span> │ │ -list_msgs │ │ -<span class="hljs-keyword">update</span> │ │ -docs.md │
	│ │ │ │ │ │ │ │
	└────────────┘ └────────────┘ └────────────┘ └────────────┘<!-- HTML_TAG_END --></pre></div> <p data-svelte-h="svelte-1qw68kx">The agent’s client can communicate with multiple servers simultaneously and compose their capabilities.</p> <h2 class="relative group"><a id="tools-vs-resources-vs-prompts-a-comparison" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#tools-vs-resources-vs-prompts-a-comparison"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Tools vs. Resources vs. Prompts: A Comparison</span></h2> <table data-svelte-h="svelte-f207d2"><thead><tr><th>Aspect</th> <th>Tools</th> <th>Resources</th> <th>Prompts</th></tr></thead> <tbody><tr><td><strong>Control</strong></td> <td>Model-controlled</td> <td>Application-controlled</td> <td>User-controlled</td></tr> <tr><td><strong>Mutability</strong></td> <td>Can modify state</td> <td>Read-only</td> <td>Static</td></tr> <tr><td><strong>Invocation</strong></td> <td>Agent decides when</td> <td>Agent requests by URI</td> <td>Host provides</td></tr> <tr><td><strong>Use Case</strong></td> <td>Actions, functions</td> <td>Data, context</td> <td>Instructions</td></tr> <tr><td><strong>Example</strong></td> <td>Call an API</td> <td>Read a file</td> <td>Code review template</td></tr></tbody></table> <h2 class="relative group"><a id="the-mcp-lifecycle" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#the-mcp-lifecycle"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>The MCP Lifecycle</span></h2> <p data-svelte-h="svelte-iehnp1">When you configure and use MCP servers:</p> <ol data-svelte-h="svelte-1jbpah5"><li><strong>Configuration</strong> — Define servers in your host/client config</li> <li><strong>Connection</strong> — Client establishes connection to each server</li> <li><strong>Discovery</strong> — Client requests list of available tools, resources, and prompts</li> <li><strong>Operation</strong> — Agent calls tools, reads resources, retrieves prompts as needed</li> <li><strong>Shutdown</strong> — Client closes connection (usually when host shuts down)</li></ol> <p data-svelte-h="svelte-7iekav">Servers can be:</p> <ul data-svelte-h="svelte-vfjtpn"><li>Started on demand (stdio servers)</li> <li>Always running (Streamable HTTP servers)</li> <li>Dynamically added or removed</li> <li>Updated without restarting the host (for Streamable HTTP)</li></ul> <h2 class="relative group"><a id="key-takeaways" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#key-takeaways"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Key Takeaways</span></h2> <p data-svelte-h="svelte-gubq5u">Hosts run agents, clients request capabilities, and servers provide them. Tools, resources, and prompts cover the range of what agents need. JSON-RPC carries the messages; stdio handles local transport and Streamable HTTP handles remote. Together they solve the M×N integration problem with a single protocol.</p> <p data-svelte-h="svelte-1avndf7">Next, we’ll build our first MCP server.</p> <a class="!text-gray-400 !no-underline text-sm flex items-center not-prose mt-4" href="https://github.com/huggingface/context-course/blob/main/units/en/unit2/key-concepts.mdx" target="_blank"><svg class="mr-1" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M31,16l-7,7l-1.41-1.41L28.17,16l-5.58-5.59L24,9l7,7z"></path><path d="M1,16l7-7l1.41,1.41L3.83,16l5.58,5.59L8,23l-7-7z"></path><path d="M12.419,25.484L17.639,6.552l1.932,0.518L14.351,26.002z"></path></svg> <span data-svelte-h="svelte-zjs2n5"><span class="underline">Update</span> on GitHub</span></a> <p></p>

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