981 pages for support.

Authorization Model Context Protocol · in the page docs/draft/tools/inspector/authorization …ion/authorization-server-discovery.md) to learn the endpoints and the supported grants. **3. Register or identify the client** The Inspector identifies itself to the authorization server through whi… CLI client Model Context Protocol · in the page docs/draft/tools/inspector/cli …ze`. A server that exposes its App tools only to clients claiming App support will then look app-less (exit `2`). Add `--advertise-apps` to claim the extension for that run. > [!NOTE] > > `tools/list… mcpdo connection client Model Context Protocol · in the page docs/draft/tools/inspector/mcpdo …oes not block other connections. ## Tasks A tool that requires task support is refused by a plain `tools/call`; add `--task` to make a task-augmented call. It still **blocks** until the task finishe… Protocol eras Model Context Protocol · in the page docs/draft/tools/inspector/protocol-eras …abilities` (including `extensions`), `instructions`, and the list of `supportedVersions`. The server's name and version arrive in the result `_meta` under `io.modelcontextprotocol/serverInfo`. . | | **Prompts** | `m` | List prompts and render them with arguments. | | **Skills** | `k` | List… Web client Model Context Protocol · in the page docs/draft/tools/inspector/web …reads content on selection, and offers **Subscribe** on servers that support subscriptions. The subscription mechanics differ by era; see [Resource subscriptions](/docs/draft/tools/inspector/protocol… Understanding Authorization in MCP Model Context Protocol · in the page docs/draft/tutorials/security/authorization …ient will fetch the metadata to learn about the authorization server, supported scopes, and other resource information. The data is typically encapsulated in a JSON blob, similar to the one below. ``… Local Server Security Model Context Protocol · in the page docs/draft/tutorials/security/local-server-security …ager, or the freedesktop Secret Service on Linux) where your client supports referencing it. * **Remember files count too.** `~/.ssh`, `~/.aws`, and similar directories are credentials on disk.… Security Best Practices Model Context Protocol · in the page docs/draft/tutorials/security/security_best_practices …protects the third-party API. It may lack dynamic client registration support, requiring the MCP proxy to use a static client ID for all requests. **Third-Party API** : The protected resource server… Build an MCP App Model Context Protocol · in the page extensions/apps/build …l-setup). ### Using an AI coding agent AI coding agents with Skills support can scaffold a complete MCP App project for you. Skills are folders of instructions and resources that your agent loads wh… MCP Apps Model Context Protocol · in the page extensions/apps/overview …rface. When a large language model (LLM) decides to call a tool that supports MCP Apps, here's what happens: 1. **UI preloading**: The tool description includes a `_meta.ui.resourceUri` field poi… Enterprise-Managed Authorization Model Context Protocol · in the page extensions/auth/enterprise-managed-authorization …revocation needed. ## Implementation guide ### For MCP clients To support Enterprise-Managed Authorization, your client must: 1. **Declare support** in its per-request capabilities: ```jsonc the… OAuth Client Credentials Model Context Protocol · in the page extensions/auth/oauth-client-credentials …s extension (`io.modelcontextprotocol/oauth-client-credentials`) adds support for the [OAuth 2.0 client credentials flow](https://datatracker.ietf.org/doc/html/rfc6749#section-4.4) to MCP. This enable… Authorization Extensions Model Context Protocol · in the page extensions/auth/overview …user authorization | Core MCP spec (no extension needed) | ## Client support Authorization extension support varies by client. See the [client matrix](/extensions/client-matrix.md) for a full breakd… Extensions Overview Model Context Protocol · in the page extensions/overview …ensions/skills/overview.md) | Discover workflow instructions and read supporting files through MCP resources. | See the [Skills overview](/extensions/skills/overview.md) to get started and the [clien… Skills Model Context Protocol · in the page extensions/skills/overview …king-groups/skills-over-mcp.md) maintains the extension. SDK and host support is still being implemented; see the [client support matrix](/extensions/client-matrix.md) and [implementations list](https… Tasks Model Context Protocol · in the page extensions/tasks/overview …erver/discover` capabilities. 2. **Task creation.** In response to a supported request, the server returns a `CreateTaskResult` (identified by `resultType: "task"`) containing a `taskId`, initi… The MCP Registry Model Context Protocol · in the page registry/about …cp`. The [Package Types guide](/registry/package-types.md) lists the supported package types and registries. More package registries may be supported in the future based on community demand. If you a… How to Authenticate When Publishing to the Official MCP Registry Model Context Protocol · in the page registry/authentication …cate before publishing to the official MCP Registry. The MCP Registry supports different authentication methods. Which authentication method you choose determines the namespace of your server's name.… The MCP Registry Moderation Policy Model Context Protocol · in the page registry/moderation-policy …uld assume minimal-to-no moderation. The MCP Registry is a community supported project, and we have limited active moderation capabilities. We largely rely on upstream package registries (like NPM, P… Quickstart: Publish an MCP Server to the MCP Registry Model Context Protocol · in the page registry/quickstart …tps://www.npmjs.com) account. * **GitHub account** — The MCP Registry supports [multiple authentication methods](/registry/authentication.md). For simplicity, this tutorial will use GitHub-based authe… MCP Registry Aggregators Model Context Protocol · in the page registry/registry-aggregators …P Registry REST API is `https://registry.modelcontextprotocol.io`. It supports the following endpoints: * [`GET /v0.1/servers`](https://registry.modelcontextprotocol.io/docs#/operations/list-servers-… Publishing Remote Servers Model Context Protocol · in the page registry/remote-servers …//github.com/modelcontextprotocol/registry/issues). The MCP Registry supports remote MCP servers via the `remotes` property in `server.json`: ```json server.json highlight={7-12} theme={null} { "$… Versioning Published MCP Servers Model Context Protocol · in the page registry/versioning …P Registry recommends [semantic versioning](https://semver.org/), but supports any version string format. When a server is published, the MCP Registry will attempt to parse its version as a semantic v… 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- …critical security vulnerabilities in MCP client implementations that support one-click installation of local MCP servers. The current MCP specification lacks explicit security requirements for client… 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 …m to open. ## Specification ### Overview Elicitation is updated to support two modes: * **Form mode** (in-band): Servers can request structured data from users with optional JSON schemas to valida… 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 …t a WG, or even to start a SEP. However, forming consensus in IG’s to support justifying the creation of a WG is often a good idea. Similarly, citing IG or WG support of a SEP helps the SEP as well.… SEP-1319: Decouple Request Payload from RPC Methods Definition Model Context Protocol · in the page seps/1319-decouple-request-payload-from-rpc-methods-definiti …imary blocker for defining bindings for other transport protocols. To support transports like **gRPC** (which is currently a [popular ask from the community](https://github.com/modelcontextprotocol/mo… SEP-1330: Elicitation Enum Schema Improvements and Standards Compliance Model Context Protocol · in the page seps/1330-elicitation-enum-schema-improvements-and-standards …n favor of JSON Schema-compliant patterns, and introducing additional support for multi-select enum schemas in addition to single choice schemas. The new schemas have been validated against the JSON s… SEP-1577: Sampling With Tools Model Context Protocol · in the page seps/1577--sampling-with-tools …ision), and reduces the complexity of client implementations (context support becoming explicitly optional). ## Motivation * [Sampling](https://modelcontextprotocol.io/specification/2025-06-18/clien… SEP-1613: Establish JSON Schema 2020-12 as Default Dialect for MCP Model Context Protocol · in the page seps/1613-establish-json-schema-2020-12-as-default-dialect-f …UST:** * Validate schemas according to declared or default dialect * Support at least JSON Schema 2020-12 ## Rationale ### Why 2020-12? 1. **Ecosystem alignment**: Python SDK (via Pydantic) and Go… SEP-1686: Tasks Model Context Protocol · in the page seps/1686-tasks …nsion ([SEP-2663](/seps/2663-tasks-extension.md)). This SEP improves support for task-based workflows in the Model Context Protocol (MCP). It introduces both the **task primitive** and the associated… SEP-1730: SDKs Tiering System Model Context Protocol · in the page seps/1730-sdks-tiering-system …ntext Protocol (MCP) SDKs to establish clear expectations for feature support, maintenance commitments, and quality standards. The system defines three tiers of SDK support with objective, measurable… SEP-1850: PR-Based SEP Workflow Model Context Protocol · in the page seps/1850-pr-based-sep-workflow …er number 2. **Open a pull request** containing the draft SEP and any supporting materials 3. **Request a sponsor** from the Maintainers list; tag potential sponsors from [MAINTAINERS.md](https://gith… SEP-1865: MCP Apps - Interactive User Interfaces for MCP Model Context Protocol · in the page seps/1865-mcp-apps-interactive-user-interfaces-for-mcp …without formal standardization: * Servers cannot reliably expect UI support via MCP * Each host may implement slightly different behaviors * Security and auditability patterns are inconsistent * Dev… SEP-2085: Governance Succession and Amendment Procedures Model Context Protocol · in the page seps/2085-governance-succession-and-amendment …voting during interregnum periods ensures major decisions have broad support during transitional periods. ### Amendment Process Design The amendment process balances stability with adaptability: *… SEP-2106: Tools `inputSchema` & `outputSchema` Conform to JSON Schema 2020-12 Model Context Protocol · in the page seps/2106-json-schema-2020-12 …s on `inputSchema`, `outputSchema`, and `structuredContent` to better support JSON Schema 2020-12. Specifically: * **`inputSchema`**: Keeps `type: "object"` required (since tool arguments are objects… SEP-2127: MCP Server Cards - HTTP Server Discovery Model Context Protocol · in the page seps/2127-mcp-server-cards …l requires a configured transport and a live connection, so it cannot support domain crawling, indexing, or pre-connection configuration. ### Proposed Solution This SEP introduces **MCP Server Cards… SEP-2133: Extensions Model Context Protocol · in the page seps/2133-extensions …by default and require explicit opt-in. SDK documentation SHOULD list supported extensions. SDK maintainers have full autonomy over extension support in their SDKs: * Maintainers are solely responsi… SEP-2148: MCP Contributor Ladder Model Context Protocol · in the page seps/2148-contributor-ladder …nominees must still secure the required sponsorship. Sponsors confirm support in the nomination issue. ### Decision-Making & Escalation #### Delegation as Default MCP operates on a principle of del… SEP-2149: MCP Group Governance and Charter Template Model Context Protocol · in the page seps/2149-working-group-charter-template …ransport Working Group exists to evolve MCP's transport mechanisms to support diverse deployment scenarios—from local subprocess communication to horizontally-scaled cloud deployments—while maintainin… SEP-2207: OIDC-Flavored Refresh Token Guidance Model Context Protocol · in the page seps/2207-oidc-refresh-token-guidance …token issuance and requests, particularly when Authorization Servers support the `offline_access` scope. The `offline_access` scope originated in OIDC but can be adopted by any OAuth 2.1 Authorizatio… SEP-2243: HTTP Header Standardization for Streamable HTTP Transport Model Context Protocol · in the page seps/2243-http-standardization …network infrastructure to work with MCP traffic using existing, well-supported mechanisms. ## Specification ### Standard Headers The Streamable HTTP transport will require POST requests to include… SEP-2260: Require Server requests to be associated with a Client request. Model Context Protocol · in the page seps/2260-Require-Server-requests-to-be-associated-with-Client-requests …. **Simplifies transport implementations** - Transports don't need to support arbitrary server-initiated request/response flows, which require a persistent connection from Server to Client; they only… SEP-2322: Multi Round-Trip Requests Model Context Protocol · in the page seps/2322-MRTR …SE streams, which cause problems in a lot of environments that cannot support long-lived connections. This proposed way of handling server-initiated requests will replace the current approach of send… SEP-2468: Recommend Issuer (iss) Parameter in MCP Auth Responses Model Context Protocol · in the page seps/2468-recommend-issuer-claim-for-auth …to validate issuer if provided and a SHOULD for authorization servers supporting MCP scenarios. Future SEPs and releases may change the SHOULD to a MUST. ## Specification ### Issuer Parameter Requir… 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 …retry on 503" excluded: "Requires fault injection; not currently supported by framework" issue: https://github.com/modelcontextprotocol/conformance/issues/N - text: "MUST be rendered in a m… SEP-2549: TTL for List Results Model Context Protocol · in the page seps/2549-TTL-for-list-results …ol/pull/2549) | *** ## Abstract This SEP proposes adding fields to support caching result objects returned by `tools/list`, `prompts/list`, `resources/list`, `resources/read`, and `resources/templa… SEP-2567: Sessionless MCP via Explicit State Handles Model Context Protocol · in the page seps/2567-sessionless-mcp …protocol version is in use and which optional capabilities each side supports — is established once per session and assumed for its duration. [SEP-2575] resolves this by removing `initialize` and car…