1,157 pages for head.
Titles and paths first, then pages whose text carries it. Each row opens that page as this site last read it.
Debugging
Model Context Protocol · in the page
docs/2025-11-25/tools/debugging
…rowser DevTools Network panel) to inspect requests, [`Mcp-Session-Id` headers](https://modelcontextprotocol.io/specification/2025-11-25/basic/transports#session-management), and SSE streams. For all…
Understanding Authorization in MCP
Model Context Protocol · in the page
docs/2025-11-25/tutorials/security/authorization
…nt in the `resource_metadata` parameter within the `WWW-Authenticate` header. ```http theme={null} HTTP/1.1 401 Unauthorized WWW-Authenticate: Bearer realm="mcp", resource_metadata="https://your-se…
Security Best Practices
Model Context Protocol · in the page
docs/2025-11-25/tutorials/security/security_best_practices
…P server: 1. The `resource_metadata` URL from the `WWW-Authenticate` header 2. The `authorization_servers` URLs from the Protected Resource Metadata document 3. The `token_endpoint`, `authorizatio…
Build an MCP client
Model Context Protocol · in the page
docs/2026-07-28/develop/build-client
…at!("{}/v1/messages", base_url.trim_end_matches('/'))) > .header("x-api-key", api_key) > .header("anthropic-version", ANTHROPIC_VERSION) > .json(&request) >…
Build an MCP server
Model Context Protocol · in the page
docs/2026-07-28/develop/build-server
…"""Make a request to the NWS API with proper error handling.""" > headers = {"User-Agent": USER_AGENT, "Accept": "application/geo+json"} > async with httpx2.AsyncClient() as client: >…
Build with Agent Skills
Model Context Protocol · in the page
docs/2026-07-28/develop/build-with-agent-skills
…none If your opening message already covers these, the agent skips ahead to the recommendation. ## Deployment paths Based on discovery, the skill recommends one of four paths and scaffolds accordi…
Architecture overview
Model Context Protocol · in the page
docs/2026-07-28/learn/architecture
…n the same machine, providing optimal performance with no network overhead. * **Streamable HTTP transport**: Uses HTTP POST for client-to-server messages with optional Server-Sent Events for streaming…
Versioning
Model Context Protocol · in the page
docs/2026-07-28/learn/versioning
…e HTTP, the same value is also carried in the [`MCP-Protocol-Version` header](https://modelcontextprotocol.io/specification/2026-07-28/basic/transports/streamable-http#protocol-version-header). Client…
MCP Inspector
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector
…hine with > no keychain (Linux without libsecret or a Secret Service, headless and SSH > sessions, Termux, and containers with a mounted volume) they are saved to > `~/.mcp-inspector/secrets.json` ins…
Authorization
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/authorization
…server answers `401`. When the response carries a `WWW-Authenticate` header, it points at the protected-resource metadata URL (`resource_metadata`) and, optionally, the scopes the request requires.…
CLI client
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/cli
…list ``` When the server comes from a file, its per-server settings (headers, timeouts, OAuth, [protocol era](https://modelcontextprotocol.io/docs/2026-07-28/tools/inspector/protocol-eras.md), and ro…
Configuration and flags
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/configuration
…lients. The web client is stricter in one respect: it also rejects `--header` and `--protocol-era` alongside a file, where the CLI and TUI apply them on top of the file's settings. > [!NOTE] > > **Wh…
Protocol eras
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/protocol-eras
…negotiated era is shown as a badge on the **Protocol** tab's Messages header and in **Connection Info**. On a modern connection, `server/discover` also supplies `capabilities` (including `extensions`)…
Recipes
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/recipes
…ector --server-url https://api.example.com/mcp --transport http \ --header "X-Tenant: acme" ``` `--transport` accepts `http` (Streamable HTTP) and `sse`. If the server is protected, see [Authorizat…
Security
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/security
…driving the backend, but a request that arrives with **no** `Origin` header (curl, a script, any non-browser client) skips that check entirely. A `Host` header allow-list runs ahead of every route, i…
TUI client
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/tui
….md#shared-server-selection-flags) (`--server-url`, `--transport`, `--header`, `-e`, `--cwd`) plus `--protocol-era` for an ad-hoc server, and the [OAuth client flags](https://modelcontextprotocol.io/d…
Web client
Model Context Protocol · in the page
docs/2026-07-28/tools/inspector/web
…ns. | | **Network** | HTTP / SSE servers | The raw HTTP view: status, headers, bodies. | | **Console** | stdio servers | The server process's `stderr`. | **Network** and **Console** never appear toge…
Understanding Authorization in MCP
Model Context Protocol · in the page
docs/2026-07-28/tutorials/security/authorization
…your server responds with `401 Unauthorized`. The `WWW-Authenticate` header can point to the [Protected Resource Metadata (PRM)](https://datatracker.ietf.org/doc/html/rfc9728) document. It should als…
Security Best Practices
Model Context Protocol · in the page
docs/2026-07-28/tutorials/security/security_best_practices
…P server: 1. The `resource_metadata` URL from the `WWW-Authenticate` header 2. The `authorization_servers` URLs from the Protected Resource Metadata document 3. The `token_endpoint`, `authorizatio…
Build an MCP client
Model Context Protocol · in the page
docs/draft/develop/build-client
…at!("{}/v1/messages", base_url.trim_end_matches('/'))) > .header("x-api-key", api_key) > .header("anthropic-version", ANTHROPIC_VERSION) > .json(&request) >…
Build an MCP server
Model Context Protocol · in the page
docs/draft/develop/build-server
…"""Make a request to the NWS API with proper error handling.""" > headers = {"User-Agent": USER_AGENT, "Accept": "application/geo+json"} > async with httpx2.AsyncClient() as client: >…
Build with Agent Skills
Model Context Protocol · in the page
docs/draft/develop/build-with-agent-skills
…none If your opening message already covers these, the agent skips ahead to the recommendation. ## Deployment paths Based on discovery, the skill recommends one of four paths and scaffolds accordi…
Architecture overview
Model Context Protocol · in the page
docs/draft/learn/architecture
…n the same machine, providing optimal performance with no network overhead. * **Streamable HTTP transport**: Uses HTTP POST for client-to-server messages with optional Server-Sent Events for streaming…
Versioning
Model Context Protocol · in the page
docs/draft/learn/versioning
…e HTTP, the same value is also carried in the [`MCP-Protocol-Version` header](https://modelcontextprotocol.io/specification/draft/basic/transports/streamable-http#protocol-version-header). Clients and…
MCP Inspector
Model Context Protocol · in the page
docs/draft/tools/inspector
…hine with > no keychain (Linux without libsecret or a Secret Service, headless and SSH > sessions, Termux, and containers with a mounted volume) they are saved to > `~/.mcp-inspector/secrets.json` ins…
Authorization
Model Context Protocol · in the page
docs/draft/tools/inspector/authorization
…server answers `401`. When the response carries a `WWW-Authenticate` header, it points at the protected-resource metadata URL (`resource_metadata`) and, optionally, the scopes the request requires.…
CLI client
Model Context Protocol · in the page
docs/draft/tools/inspector/cli
…list ``` When the server comes from a file, its per-server settings (headers, timeouts, OAuth, [protocol era](https://modelcontextprotocol.io/docs/draft/tools/inspector/protocol-eras.md), and roots)…
Configuration and flags
Model Context Protocol · in the page
docs/draft/tools/inspector/configuration
…lients. The web client is stricter in one respect: it also rejects `--header` and `--protocol-era` alongside a file, where the CLI and TUI apply them on top of the file's settings. > [!NOTE] > > **Wh…
Protocol eras
Model Context Protocol · in the page
docs/draft/tools/inspector/protocol-eras
…negotiated era is shown as a badge on the **Protocol** tab's Messages header and in **Connection Info**. On a modern connection, `server/discover` also supplies `capabilities` (including `extensions`)…
Recipes
Model Context Protocol · in the page
docs/draft/tools/inspector/recipes
…ector --server-url https://api.example.com/mcp --transport http \ --header "X-Tenant: acme" ``` `--transport` accepts `http` (Streamable HTTP) and `sse`. If the server is protected, see [Authorizat…
Security
Model Context Protocol · in the page
docs/draft/tools/inspector/security
…driving the backend, but a request that arrives with **no** `Origin` header (curl, a script, any non-browser client) skips that check entirely. A `Host` header allow-list runs ahead of every route, i…
TUI client
Model Context Protocol · in the page
docs/draft/tools/inspector/tui
….md#shared-server-selection-flags) (`--server-url`, `--transport`, `--header`, `-e`, `--cwd`) plus `--protocol-era` for an ad-hoc server, and the [OAuth client flags](https://modelcontextprotocol.io/d…
Web client
Model Context Protocol · in the page
docs/draft/tools/inspector/web
…ns. | | **Network** | HTTP / SSE servers | The raw HTTP view: status, headers, bodies. | | **Console** | stdio servers | The server process's `stderr`. | **Network** and **Console** never appear toge…
Understanding Authorization in MCP
Model Context Protocol · in the page
docs/draft/tutorials/security/authorization
…your server responds with `401 Unauthorized`. The `WWW-Authenticate` header can point to the [Protected Resource Metadata (PRM)](https://datatracker.ietf.org/doc/html/rfc9728) document. It should als…
Security Best Practices
Model Context Protocol · in the page
docs/draft/tutorials/security/security_best_practices
…P server: 1. The `resource_metadata` URL from the `WWW-Authenticate` header 2. The `authorization_servers` URLs from the Protected Resource Metadata document 3. The `token_endpoint`, `authorizatio…
Build an MCP App
Model Context Protocol · in the page
extensions/apps/build
…heme={null} <!-- mcp-app.html --> <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8" /> <title>Get Time App</title> </head> <body> <p> <strong>Server Time:</strong>…
OAuth Client Credentials
Model Context Protocol · in the page
extensions/auth/oauth-client-credentials
…ver. **3. Include the token** Pass the token in the `Authorization` header of HTTP requests to the MCP server: ``` Authorization: Bearer <access_token> ``` **4. Handle token refresh** Client cred…
Skills
Model Context Protocol · in the page
extensions/skills/overview
…ests and sizes match the manifest. Hosts **MUST NOT** retrieve files ahead of need, including on connection, listing, or approval. Approval binds to the manifest without requiring file retrieval. ###…
Publishing Remote Servers
Model Context Protocol · in the page
registry/remote-servers
…"default": "us-east-1" } } } ] } ``` ## HTTP Headers MCP clients can be instructed to send specific HTTP headers by adding the `headers` property to the `remotes` entry: ```…
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
…or text inputs, numbers, and enum selections leading to more user overhead. ### Real-World Example Consider implementing an email reply function. Without elicitation, the tool becomes unwieldy: ```…
SEP-1046: Support OAuth client credentials flow in authorization
Model Context Protocol · in the page
seps/1046-support-oauth-client-credentials-flow-in-authoriza
…er RFCs that can define these profiles. The other RFCs include [WIMSE Headless JWT Authentication](https://www.ietf.org/archive/id/draft-levy-wimse-headless-jwt-authentication-01.html) (for specifying…
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
…ce --> Retire (good idea but stale; would be good for someone to spearhead a new Working Group) * Security --> Interest Group (perhaps with Security Best Practices WG?) * Transports --> Interest Group…
SEP-1319: Decouple Request Payload from RPC Methods Definition
Model Context Protocol · in the page
seps/1319-decouple-request-payload-from-rpc-methods-definiti
…another for gRPC), which would introduce significant maintenance overhead and risk inconsistencies. Crucially, this design refactors the specification document itself but intentionally **leaves the…
SEP-1330: Elicitation Enum Schema Improvements and Standards Compliance
Model Context Protocol · in the page
seps/1330-elicitation-enum-schema-improvements-and-standards
…ce enums. 3. **Client Implementation:** shows that the additional overhead of implementing a group of checkboxes v/s a single checkbox is minimal: [https://github.com/evalstate/fast-agent/pull/324/fil…
SEP-1577: Sampling With Tools
Model Context Protocol · in the page
seps/1577--sampling-with-tools
…/document/d/1KUsloHpsjR4fdXdJuofb9jUuK0XWi88clbRm9sWE510/edit?tab=t.0#heading=h.edw7oyac2e87)): it makes it particularly tricky to fully implement sampling, which along with other precautions needed f…
SEP-1686: Tasks
Model Context Protocol · in the page
seps/1686-tasks
…he existing workflow-management system. * **Reduce Implementation Overhead:** Server implementers don't need to build new state management, persistence, or monitoring infrastructure. They can focus on…
SEP-1850: PR-Based SEP Workflow
Model Context Protocol · in the page
seps/1850-pr-based-sep-workflow
…e commit to rename the file to `{PR-number}-{slug}.md` and update the header (`SEP-{PR-number}` and `PR: #{PR-number}`) 5. **Wait for sponsor assignment**: Once a sponsor agrees, they will assign them…
SEP-2127: MCP Server Cards - HTTP Server Discovery
Model Context Protocol · in the page
seps/2127-mcp-server-cards
…/ `repository` / `websiteUrl`), its remote transport endpoints (URLs, headers, variable templates, supported protocol versions), and optional namespaced `_meta` data. `_meta` is not used to advertise…
SEP-2149: MCP Group Governance and Charter Template
Model Context Protocol · in the page
seps/2149-working-group-charter-template
…community members to understand any group's operations * Reduces overhead for forming new groups * Creates accountability through explicit documentation ### Why Explicit Authority Tables? The autho…
SEP-2207: OIDC-Flavored Refresh Token Guidance
Model Context Protocol · in the page
seps/2207-oidc-refresh-token-guidance
…t and Authorization Server. Including it in the `WWW-Authenticate` header's `scope` parameter or in the Protected Resource Metadata's `scopes_supported` would be semantically incorrect since…