599 pages for tail.

SEP-2322: Multi Round-Trip Requests Model Context Protocol · in the page seps/2322-MRTR …ending in parallel (e.g., a tool list or even another tool call). <details> <summary>Click to expand Example Flow for Ephemeral Tools</summary> <b>Example Flow for Ephemeral Tools</b> Note: Th… SEP-2575: Make MCP Stateless Model Context Protocol · in the page seps/2575-stateless-mcp …equests. */ supportedVersions: string[]; /** * An object detailing the capabilities of the server. */ capabilities: ServerCapabilities; /** * Information about the server softwar… SEP-2663: Tasks Extension Model Context Protocol · in the page seps/2663-tasks-extension …atus * - Additional information for "failed" status (e.g., error details, what went wrong) * * This MAY be exposed to the end-user or model. */ statusMessage?: string; /** ISO 8601 ti… Overview Model Context Protocol · in the page specification/2024-11-05/basic/index …t exactly the features they need. See the following pages for more details on the different components: <CardGroup cols={3}> <Card title="Lifecycle" icon="arrows-rotate" href="/specification/2024-… Lifecycle Model Context Protocol · in the page specification/2024-11-05/basic/lifecycle …bility * Exchange and negotiate capabilities * Share implementation details The client **MUST** initiate this phase by sending an `initialize` request containing: * Protocol version supported * Clie… Specification Model Context Protocol · in the page specification/2024-11-05/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateful connections * Server and client capabil… Overview Model Context Protocol · in the page specification/2024-11-05/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/2024-11-05/server/prompts" /> <Ca… Logging Model Context Protocol · in the page specification/2024-11-05/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress… Authorization Model Context Protocol · in the page specification/2025-03-26/basic/authorization …server, or 2. Present a UI to users that allows them to enter these details, after registering an OAuth client themselves (e.g., through a configuration interface hosted by the server). ### Aut… Lifecycle Model Context Protocol · in the page specification/2025-03-26/basic/lifecycle …bility * Exchange and negotiate capabilities * Share implementation details The client **MUST** initiate this phase by sending an `initialize` request containing: * Protocol version supported * Clie… Key Changes Model Context Protocol · in the page specification/2025-03-26/changelog …tocol/specification/tree/main/schema/2025-03-26/schema.ts) for more details. ## Full changelog For a complete list of all changes that have been made since the last protocol revision, [see GitHub](h… Specification Model Context Protocol · in the page specification/2025-03-26/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateful connections * Server and client capabil… Overview Model Context Protocol · in the page specification/2025-03-26/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/2025-03-26/server/prompts" /> <Ca… Logging Model Context Protocol · in the page specification/2025-03-26/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress… Authorization Model Context Protocol · in the page specification/2025-06-18/basic/authorization …issuing access tokens for use at the MCP server. The implementation details of the authorization server are beyond the scope of this specification. It may be hosted with the resource server or a separ… Lifecycle Model Context Protocol · in the page specification/2025-06-18/basic/lifecycle …bility * Exchange and negotiate capabilities * Share implementation details The client **MUST** initiate this phase by sending an `initialize` request containing: * Protocol version supported * Clie… Specification Model Context Protocol · in the page specification/2025-06-18/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateful connections * Server and client capabil… Schema Reference Model Context Protocol · in the page specification/2025-06-18/schema …the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div></li></ul></div></section> </div> <div class="type"> ### `JSONRPCMessa… Overview Model Context Protocol · in the page specification/2025-06-18/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/2025-06-18/server/prompts" /> <Ca… Logging Model Context Protocol · in the page specification/2025-06-18/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress… Authorization Model Context Protocol · in the page specification/2025-11-25/basic/authorization …issuing access tokens for use at the MCP server. The implementation details of the authorization server are beyond the scope of this specification. It may be hosted with the resource server or a separ… Lifecycle Model Context Protocol · in the page specification/2025-11-25/basic/lifecycle …bility * Exchange and negotiate capabilities * Share implementation details The client **MUST** initiate this phase by sending an `initialize` request containing: * Protocol version supported * Clie… Transports Model Context Protocol · in the page specification/2025-11-25/basic/transports …025-11-25/basic/security_best_practices#session-hijacking) for more details. 2. If an `MCP-Session-Id` is returned by the server during initialization, clients using the Streamable HTTP transport *… Tasks Model Context Protocol · in the page specification/2025-11-25/basic/utilities/tasks …g the current state (can be present for any status, including error details for failed tasks) * `createdAt`: ISO 8601 timestamp when the task was created * `ttl`: Time in milliseconds from creation be… Elicitation Model Context Protocol · in the page specification/2025-11-25/client/elicitation …the `url` field in a URL elicitation request (with the restrictions detailed above). ### Identifying the User Servers **MUST NOT** rely on client-provided user identification without server verifica… Specification Model Context Protocol · in the page specification/2025-11-25/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateful connections * Server and client capabil… Schema Reference Model Context Protocol · in the page specification/2025-11-25/schema …the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div></section> </div> <div class="type"> ### `Icon` <div class="tsd-sig… Overview Model Context Protocol · in the page specification/2025-11-25/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/2025-11-25/server/prompts" /> <Ca… Logging Model Context Protocol · in the page specification/2025-11-25/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress… Authorization Server Discovery Model Context Protocol · in the page specification/2026-07-28/basic/authorization/authorization-server-discovery …atracker.ietf.org/doc/html/rfc9728)) for guidance on implementation details. Implementors should note that Protected Resource Metadata documents can define multiple authorization servers. The respons… Client Registration Model Context Protocol · in the page specification/2026-07-28/basic/authorization/client-registration …server, or 2. Present a UI to users that allows them to enter these details, after registering an OAuth client themselves (e.g., through a configuration interface hosted by the server). ## Dyna… Authorization Model Context Protocol · in the page specification/2026-07-28/basic/authorization/index …issuing access tokens for use at the MCP server. The implementation details of the authorization server are beyond the scope of this specification. It may be hosted with the resource server or a separ… Authorization Security Considerations Model Context Protocol · in the page specification/2026-07-28/basic/authorization/security-considerations …, authorization servers **MUST** consider the security implications detailed in [OAuth Client ID Metadata Document, Section 6](https://datatracker.ietf.org/doc/html/draft-ietf-oauth-client-id-metadata… Streamable HTTP Model Context Protocol · in the page specification/2026-07-28/basic/transports/streamable-http …tool's `inputSchema`. See [Tool Definitions][tool-definitions] for details on how to annotate tool parameters. While the use of `x-mcp-header` is optional for servers, clients **MUST** support this… Elicitation Model Context Protocol · in the page specification/2026-07-28/client/elicitation …the `url` field in a URL elicitation request (with the restrictions detailed above). ### Identifying the User Servers **MUST NOT** rely on client-provided user identification without server verifica… Specification Model Context Protocol · in the page specification/2026-07-28/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateless, self-contained requests * Per-request… Schema Reference Model Context Protocol · in the page specification/2026-07-28/schema …/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</p> </div></div> </div> <div class="type"> ### `NotificationMetaObject` <div class="tsd-signature"><span class="tsd-s… Overview Model Context Protocol · in the page specification/2026-07-28/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/2026-07-28/server/prompts" /> <Ca… Logging Model Context Protocol · in the page specification/2026-07-28/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress… Authorization Server Discovery Model Context Protocol · in the page specification/draft/basic/authorization/authorization-server-discovery …atracker.ietf.org/doc/html/rfc9728)) for guidance on implementation details. Implementors should note that Protected Resource Metadata documents can define multiple authorization servers. The respons… Client Registration Model Context Protocol · in the page specification/draft/basic/authorization/client-registration …server, or 2. Present a UI to users that allows them to enter these details, after registering an OAuth client themselves (e.g., through a configuration interface hosted by the server). ## Dyna… Authorization Model Context Protocol · in the page specification/draft/basic/authorization/index …issuing access tokens for use at the MCP server. The implementation details of the authorization server are beyond the scope of this specification. It may be hosted with the resource server or a separ… Authorization Security Considerations Model Context Protocol · in the page specification/draft/basic/authorization/security-considerations …, authorization servers **MUST** consider the security implications detailed in [OAuth Client ID Metadata Document, Section 6](https://datatracker.ietf.org/doc/html/draft-ietf-oauth-client-id-metadata… Streamable HTTP Model Context Protocol · in the page specification/draft/basic/transports/streamable-http …tool's `inputSchema`. See [Tool Definitions][tool-definitions] for details on how to annotate tool parameters. While the use of `x-mcp-header` is optional for servers, clients **MUST** support this… Elicitation Model Context Protocol · in the page specification/draft/client/elicitation …the `url` field in a URL elicitation request (with the restrictions detailed above). ### Identifying the User Servers **MUST NOT** rely on client-provided user identification without server verifica… Specification Model Context Protocol · in the page specification/draft/index …al context and tools into the ecosystem of AI applications. ## Key Details ### Base Protocol * [JSON-RPC](https://www.jsonrpc.org/) message format * Stateless, self-contained requests * Per-request… Schema Reference Model Context Protocol · in the page specification/draft/schema …/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</p> </div></div> </div> <div class="type"> ### `NotificationMetaObject` <div class="tsd-signature"><span class="tsd-s… Overview Model Context Protocol · in the page specification/draft/server/index …POST requests, file writing | Explore these key primitives in more detail below: <CardGroup cols={3}> <Card title="Prompts" icon="message" href="/specification/draft/server/prompts" /> <Card ti… Logging Model Context Protocol · in the page specification/draft/server/utilities/logging …---------------------- | -------------------------- | | debug | Detailed debugging information | Function entry/exit points | | info | General informational messages | Operation progress…