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Koichi ITO c9d36b04bf [Doc] Align the Docs Page Names With the MCP Specification

Three pages carried names the 2026-07-28 specification does not use: "Multi-Round-Trip Results" for
the pattern the specification titles Multi Round-Trip Requests (MRTR) and serves at basic/patterns/mrtr -
the results are the `InputRequiredResult` wire type, not the feature - plus "Completions" for the utility
the specification titles Completion, and "Notification Subscriptions" for the pattern it titles Subscriptions.
Retitle the three pages to the specification's names, move them to /server/mrtr/ and /client/mrtr/,
/server/completion/, and /server/subscriptions/ following the specification's slugs, update every internal reference,
and keep the URLs published with v1.3.0 working via jekyll-redirect-from.
The Discovery page keeps its title but moves from /server/discovery/ to /server/discover/, matching
the specification's slug and the `server/discover` RPC, with its published URL redirected the same way.

2026-08-22 18:07:38 +09:00

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layout	title	nav_order
default	Notifications	11

Notifications

The server supports sending notifications to clients when lists of tools, prompts, or resources change. This enables real-time updates without polling.

Notification Methods

The server provides the following notification methods:

notify_tools_list_changed - Send a notification when the tools list changes
notify_prompts_list_changed - Send a notification when the prompts list changes
notify_resources_list_changed - Send a notification when the resources list changes
notify_log_message - Send a structured logging notification message (see Logging)

Session Scoping

When using Streamable HTTP transport with multiple clients, each client connection gets its own session. Notifications are scoped as follows:

report_progress and notify_log_message called via server_context inside a tool handler are automatically sent only to the requesting client. No extra configuration is needed.
notify_tools_list_changed, notify_prompts_list_changed, and notify_resources_list_changed are always broadcast to all connected clients, as they represent server-wide state changes. These should be called on the server instance directly.

On the modern lifecycle (MCP 2026-07-28), clients receive these broadcasts through the subscriptions/listen stream; see Subscriptions.

Notification Format

Notifications follow the JSON-RPC 2.0 specification and use these method names:

notifications/tools/list_changed
notifications/prompts/list_changed
notifications/resources/list_changed
notifications/cancelled (see Cancellation)
notifications/progress (see Progress)
notifications/message (see Logging)

Broadcasting a List Change

Call the matching notify_* method after changing a server-wide list:

server = MCP::Server.new(name: "my_server")

# Default Streamable HTTP - session oriented
transport = MCP::Server::Transports::StreamableHTTPTransport.new(server)

# When tools change, notify clients
server.define_tool(name: "new_tool") { |**args| MCP::Tool::Response.new([{ type: "text", text: "ok" }]) }
server.notify_tools_list_changed

# When prompts change, notify clients
server.define_prompt(name: "new_prompt") do |args, server_context:|
  MCP::Prompt::Result.new(messages: [])
end
server.notify_prompts_list_changed

# When resources change, notify clients
server.define_resource(uri: "resource://new", name: "new_resource", mime_type: "text/plain") do
  [MCP::Resource::TextContents.new(uri: "resource://new", mime_type: "text/plain", text: "contents")]
end
server.notify_resources_list_changed

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