1,295 pages for code.

Recipes Model Context Protocol · in the page docs/draft/tools/inspector/recipes …ead of retyping them. It parses Claude Desktop, Cursor, Cline, and VS Code client configs directly, and it also reads a server's own [MCP Registry](/registry/about) `server.json`. Import merges into… Security Model Context Protocol · in the page docs/draft/tools/inspector/security …ile, the key, or the process memory holding decrypted values | No | | Code running as the same user | No | | A weak passphrase: anyone holding the file can guess offline, quickly, because the scrypt c… Web client Model Context Protocol · in the page docs/draft/tools/inspector/web …etwork**: the HTTP layer, for SSE and Streamable HTTP servers. Status codes, request and response headers, and bodies. On modern connections the standardized `Mcp-*` headers are highlighted and sentin… Understanding Authorization in MCP Model Context Protocol · in the page docs/draft/tutorials/security/authorization …["http://localhost:3000/callback"], "grant_types": ["authorization_code", "refresh_token"], "response_types": ["code"] } ``` If the registration succeeds, the authorization server will return a… Local Server Security Model Context Protocol · in the page docs/draft/tutorials/security/local-server-security …l: **your machine**. When you run an MCP server locally, you download code from the internet and run it as a child process of your user account. That process inherits your environment variables, can r… Security Best Practices Model Context Protocol · in the page docs/draft/tutorials/security/security_best_practices …ilities. This attack allows malicious clients to obtain authorization codes without proper user consent by exploiting the combination of static client IDs, dynamic client registration, and consent coo… Build an MCP App Model Context Protocol · in the page extensions/apps/build …rate your project. **1. Install the skill** If you are using Claude Code, you can install the skill directly with: ``` /plugin marketplace add modelcontextprotocol/ext-apps /plugin install mcp-apps… MCP Apps Model Context Protocol · in the page extensions/apps/overview …now?" **Multi-step workflows.** Approving expense reports, reviewing code changes, or triaging issues involves examining items one by one. An MCP App provides navigation controls, action buttons, and… Enterprise-Managed Authorization Model Context Protocol · in the page extensions/auth/enterprise-managed-authorization …IdP Note over IdP: User Logs In IdP-->>UA: IdP Authorization Code UA->>C: IdP Authorization Code C->>IdP: Token Request with IdP Authorization Code IdP-->>C: ID Token note ov… OAuth Client Credentials Model Context Protocol · in the page extensions/auth/oauth-client-credentials …educe risk: > > * Store secrets in a secrets manager, never in source code or environment files checked into version control. > * Rotate secrets on a regular schedule and immediately after any suspect… Authorization Extensions Model Context Protocol · in the page extensions/auth/overview …cific real-world scenarios where the standard OAuth 2.0 authorization code flow isn't the right fit. > **[modelcontextprotocol/ext-auth](https://github.com/modelcontextprotocol/ext-auth)** > > Source… Extension Support Matrix Model Context Protocol · in the page extensions/client-matrix …| | | | [Claude Desktop](https://claude.ai/download) | | | | | | [VS Code GitHub Copilot](https://code.visualstudio.com/) | | | | | | [Microsoft 365 Copilot](https://www.microsoft.com/microsoft-365-c… Skills Model Context Protocol · in the page extensions/skills/overview …that combine several tools or require supporting references, such as code review or document processing. Serving them over MCP keeps those instructions with the service they describe. Clients can dis… The MCP Registry Model Context Protocol · in the page registry/about …e registries — such as npm, PyPI, and Docker Hub — host packages with code and binaries. The MCP Registry hosts metadata that points to those packages. For example, a `weather-mcp` package could be… How to Authenticate When Publishing to the Official MCP Registry Model Context Protocol · in the page registry/authentication …henticate, please: 1. Go to: https://github.com/login/device 2. Enter code: ABCD-1234 3. Authorize this application Waiting for authorization... ``` Visit the link, follow the prompts, and enter the… How to Automate Publishing with GitHub Actions Model Context Protocol · in the page registry/github-actions …uthentication contents: read steps: - name: Checkout code uses: actions/checkout@v5 ### Publish underlying npm package: - name: Set up Node.js uses: acti… Quickstart: Publish an MCP Server to the MCP Registry Model Context Protocol · in the page registry/quickstart …henticate, please: 1. Go to: https://github.com/login/device 2. Enter code: ABCD-1234 3. Authorize this application Waiting for authorization... ``` Visit the link, follow the prompts, and enter the… MCP Registry Aggregators Model Context Protocol · in the page registry/registry-aggregators …path parameters such as `serverName` and `version` **must** be URL-encoded. For example, `io.modelcontextprotocol/everything` must be encoded as `io.modelcontextprotocol%2Feverything`. Aggregators w… Official MCP Registry Terms of Service Model Context Protocol · in the page registry/terms-of-service …GitHub repository has, or perform automated security scanning on your code. By publishing a server, you agree that others may engage in this sort of processing, and you waive rights you might have in… SEP-1024: MCP Client Security Requirements for Local Server Installation Model Context Protocol · in the page seps/1024-mcp-client-security-requirements-for-local-server- …making them susceptible to malicious configurations. 4. **Arbitrary Code Execution**: Attackers can embed harmful commands in MCP server configurations and distribute them through legitimate channel… SEP-1034: Support default values for all primitive types in elicitation schemas Model Context Protocol · in the page seps/1034--support-default-values-for-all-primitive-types-in …thread_id: str, content: Optional[str] = "" ) -> None: # Code can lookup the participants from the original thread # and prepare an elicitation request with the defaults setup ``` ``… SEP-1036: URL Mode Elicitation for secure out-of-band interactions Model Context Protocol · in the page seps/1036-url-mode-elicitation-for-secure-out-of-band-intera …completed, the server **MAY** return a `URLElicitationRequiredError` (code `-32042`) to indicate that a URL mode elicitation is required. The server **MUST NOT** return this error except when URL mode… SEP-1302: Formalize Working Groups and Interest Groups in MCP Governance Model Context Protocol · in the page seps/1302-formalize-working-groups-and-interest-groups-in-mc …reaching consensus on the specification and rationale before writing code, the principle of “rough consensus and running code” is still useful when it comes to resolving many discussions of protocol… SEP-1303: Input Validation Errors as Tool Execution Errors Model Context Protocol · in the page seps/1303-input-validation-errors-as-tool-execution-errors …; if (date.getTime() < Date.now()) { ctx.addIssue({ code: z.ZodIssueCode.custom, message: "Dates must be in the future. Current date is " + formatDateFr(n… SEP-1319: Decouple Request Payload from RPC Methods Definition Model Context Protocol · in the page seps/1319-decouple-request-payload-from-rpc-methods-definiti …e specification and on tools that parse the specification to generate code or documentation. SEP-1577: Sampling With Tools Model Context Protocol · in the page seps/1577--sampling-with-tools …* This guarantees wire-level backwards-compatibility * Existing code that uses sampling may break w/ new SDK releases as it will need to test content to know if it's an array or a single block,… SEP-1686: Tasks Model Context Protocol · in the page seps/1686-tasks …rimental tasks feature shipped in the `2025-11-25` specification. The code examples below are non-normative pseudocode written against the v1 SDKs. The draft specification moves tasks out of the core… SEP-1850: PR-Based SEP Workflow Model Context Protocol · in the page seps/1850-pr-based-sep-workflow …? Storing SEPs as files keeps authoritative specs versioned with the code, mirroring successful processes used by PEPs (Python Enhancement Proposals) and other standards bodies. This approach: * Pro… SEP-2106: Tools `inputSchema` & `outputSchema` Conform to JSON Schema 2020-12 Model Context Protocol · in the page seps/2106-json-schema-2020-12 …ange for typed consumers**, even though the wire format is unchanged. Code such as: ```typescript theme={null} const result = await client.callTool({ name: "get_weather", arguments: { ... } }); const… SEP-2148: MCP Contributor Ladder Model Context Protocol · in the page seps/2148-contributor-ladder …ustained engagement, not tenure alone * **Multiple Growth Pathways**: Code, specification work, documentation, and community building all lead to advancement * **Transparency**: Criteria for advanceme… SEP-2149: MCP Group Governance and Charter Template Model Context Protocol · in the page seps/2149-working-group-charter-template …ing Groups produce concrete deliverables — SEPs, implementations, and code. Interest Groups facilitate discussion and knowledge-sharing to identify problems and gather requirements. The governance rul… SEP-2207: OIDC-Flavored Refresh Token Guidance Model Context Protocol · in the page seps/2207-oidc-refresh-token-guidance …requesting refresh tokens**: Major MCP clients (Cursor, Claude, VS Code, etc.) aren't explicitly asking for refresh tokens via the `offline_access` scope because they don't know whether the Auth… SEP-2243: HTTP Header Standardization for Streamable HTTP Transport Model Context Protocol · in the page seps/2243-http-standardization …f3a4b5c-6d7e-8f9a-0b1c-2d3e4f5a6b7c Mcp-Method: prompts/get Mcp-Name: code_review { "jsonrpc": "2.0", "id": 3, "method": "prompts/get", "params": { "name": "code_review", "arguments":… SEP-2322: Multi Round-Trip Requests Model Context Protocol · in the page seps/2322-MRTR …yer integration, which means that it's very hard to write in-line code via the SDKs. * **Statefulness in Load Balancing**: With the use of cookies, it is possible for the load balancing layer to… SEP-2468: Recommend Issuer (iss) Parameter in MCP Auth Responses Model Context Protocol · in the page seps/2468-recommend-issuer-claim-for-auth …jected until the host extracts `iss` from the redirect URI alongside `code`. SDKs are expected to widen callback signatures additively (e.g., an optional `iss` argument) so existing call sites continu… SEP-2484: Require Conformance Tests for Standards Track SEPs to Reach Final Status Model Context Protocol · in the page seps/2484-conformance-tests-required-for-final-seps …on is written in English. SDK maintainers translate that English into code, and every translation is an opportunity for drift. SEP-1730 (SDK Tiering) already depends on conformance tests (Tier 1 requi… SEP-2567: Sessionless MCP via Explicit State Handles Model Context Protocol · in the page seps/2567-sessionless-mcp …e pattern works best when: * **Handles are opaque.** A handle that encodes internal structure (`cart_user42_2026-03-11`) invites clients to parse it or models to guess it; an opaque handle such as `b… SEP-2575: Make MCP Stateless Model Context Protocol · in the page seps/2575-stateless-mcp …and memory leaks. * **Client-side:** Developers must write complex code to manage a persistent connection and handle the inevitable network failures and reconnections, including the logic… SEP-2640: Skills Extension Model Context Protocol · in the page seps/2640-skills-extension …s skill content, whether a cache directory or a virtual mount, MUST encode the server identity as well as the `uri`, so that same-URI skills from different servers land at distinct paths and the origi… SEP-2663: Tasks Extension Model Context Protocol · in the page seps/2663-tasks-extension …ning `CreateTaskResult`, the server **MUST** return an error with the code `-32021` (Missing Required Client Capability), indicating the required extension in the error response: ```jsonl theme={null… SEP-414: Document OpenTelemetry Trace Context Propagation Conventions Model Context Protocol · in the page seps/414-request-meta …Track | | **Created** | 2025-04-25 | | **Author(s)** | Adrian Cole ([@codefromthecrypt](https://github.com/codefromthecrypt)) | | **Sponsor** | Marcelo Trylesinski ([@Kludex](https://github.com/Kludex… SEP-973: Expose additional metadata for Implementations, Resources, Tools and Prompts Model Context Protocol · in the page seps/973-expose-additional-metadata-for-implementations-res …cript theme={null} /** * A url pointing to an icon URL or a base64-encoded data URI * * Clients that support rendering icons MUST support at least the following MIME types: * - image/png - PNG ima… SEP-986: Specify Format for Tool Names Model Context Protocol · in the page seps/986-specify-format-for-tool-names …\_, -, ., and /—is based on patterns used in major clients (e.g., VS Code, Claude) and aligns with common conventions in programming and APIs. Restricting spaces and commas avoids parsing issues and… SEP-990: Enable enterprise IdP policy controls during MCP OAuth flows Model Context Protocol · in the page seps/990-enable-enterprise-idp-policy-controls-during-mcp-o …IdP Note over IdP: User Logs In IdP-->>-UA: IdP Authorization Code UA->>C: IdP Authorization Code C->>+IdP: Token Request with IdP Authorization Code IdP-->-C: ID Token end… SEP-991: Enable URL-based Client Registration using OAuth Client ID Metadata Documents Model Context Protocol · in the page seps/991-enable-url-based-client-registration-using-oauth-c …er->>Server: Approves access Server->>Client: Authorization code via redirect_uri Client->>Server: Exchange code for token<br/>client_id=https://app.example.com/oauth/metadata.json… SEP-994: Shared Communication Practices/Guidelines Model Context Protocol · in the page seps/994-shared-communication-practicesguidelines …, protocol vulnerabilities) * People matters (maintainer discussions, code of conduct) * Coordination requiring immediate focused response All technical and governance decisions must be documented pu… Specification Enhancement Proposals (SEPs) Model Context Protocol · in the page seps/index …2164-resource-not-found-error) | Standardize Resource Not Found Error Code | Final | Standards Track | 2026-01-28 | | [SEP-2149](/seps/2149-working-group-charter-template) | MCP Group Governance and C… Architecture Model Context Protocol · in the page specification/2024-11-05/architecture/index …ze implementation overhead * Clear separation enables maintainable code 2. **Servers should be highly composable** * Each server provides focused functionality in isolation * Multiple server… Overview Model Context Protocol · in the page specification/2024-11-05/basic/index …follow any JSON object structure, while errors must include an error code and message at minimum. ## Protocol Layers The Model Context Protocol consists of several key components that work together… Lifecycle Model Context Protocol · in the page specification/2024-11-05/basic/lifecycle …`json theme={null} { "jsonrpc": "2.0", "id": 1, "error": { "code": -32602, "message": "Unsupported protocol version", "data": { "supported": ["2024-11-05"], "requested":…