mcp: finalize MCP server definition provider API

src/vs/platform/extensions/common/extensionsApiProposals.ts

@@ -242,9 +242,6 @@ const _allApiProposals = {
 	mappedEditsProvider: {
 		proposal: 'https://raw.githubusercontent.com/microsoft/vscode/main/src/vscode-dts/vscode.proposed.mappedEditsProvider.d.ts',
 	},
-	mcpConfigurationProvider: {
-		proposal: 'https://raw.githubusercontent.com/microsoft/vscode/main/src/vscode-dts/vscode.proposed.mcpConfigurationProvider.d.ts',
-	},
 	multiDocumentHighlightProvider: {
 		proposal: 'https://raw.githubusercontent.com/microsoft/vscode/main/src/vscode-dts/vscode.proposed.multiDocumentHighlightProvider.d.ts',
 	},

src/vs/workbench/api/common/extHost.api.impl.ts

@@ -1528,14 +1528,10 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				return extHostLanguageModels.registerIgnoredFileProvider(extension, provider);
 			},
 			registerMcpServerDefinitionProvider(id, provider) {
-				checkProposedApiEnabled(extension, 'mcpConfigurationProvider');
 				return extHostMcp.registerMcpConfigurationProvider(extension, id, provider);
 			}
 		};
 
-		// todo@connor4312: proposed API back-compat
-		(lm as any).registerMcpConfigurationProvider = lm.registerMcpServerDefinitionProvider;
-
 		// namespace: speech
 		const speech: typeof vscode.speech = {
 			registerSpeechProvider(id: string, provider: vscode.SpeechProvider) {

src/vscode-dts/vscode.d.ts

@@ -20213,6 +20213,139 @@ declare module 'vscode' {
 		toolMode?: LanguageModelChatToolMode;
 	}
 
+	/**
+	 * McpStdioServerDefinition represents an MCP server available by running
+	 * a local process and operating on its stdin and stdout streams. The process
+	 * will be spawned as a child process of the extension host and by default
+	 * will not run in a shell environment.
+	 */
+	export class McpStdioServerDefinition {
+		/**
+		 * The human-readable name of the server.
+		 */
+		readonly label: string;
+
+		/**
+		 * The working directory used to start the server.
+		 */
+		cwd?: Uri;
+
+		/**
+		 * The command used to start the server. Node.js-based servers may use
+		 * `process.execPath` to use the editor's version of Node.js to run the script.
+		 */
+		command: string;
+
+		/**
+		 * Additional command-line arguments passed to the server.
+		 */
+		args: string[];
+
+		/**
+		 * Optional additional environment information for the server. Variables
+		 * in this environment will overwrite or remove (if null) the default
+		 * environment variables of the editor's extension host.
+		 */
+		env: Record<string, string | number | null>;
+
+		/**
+		 * Optional version identification for the server. If this changes, the
+		 * editor will indicate that tools have changed and prompt to refresh them.
+		 */
+		version?: string;
+
+		/**
+		 * @param label The human-readable name of the server.
+		 * @param command The command used to start the server.
+		 * @param args Additional command-line arguments passed to the server.
+		 * @param env Optional additional environment information for the server.
+		 * @param version Optional version identification for the server.
+		 */
+		constructor(label: string, command: string, args?: string[], env?: Record<string, string | number | null>, version?: string);
+	}
+
+	/**
+	 * McpHttpServerDefinition represents an MCP server available using the
+	 * Streamable HTTP transport.
+	 */
+	export class McpHttpServerDefinition {
+		/**
+		 * The human-readable name of the server.
+		 */
+		readonly label: string;
+
+		/**
+		 * The URI of the server. The editor will make a POST request to this URI
+		 * to begin each session.
+		 */
+		uri: Uri;
+
+		/**
+		 * Optional additional heads included with each request to the server.
+		 */
+		headers: Record<string, string>;
+
+		/**
+		 * Optional version identification for the server. If this changes, the
+		 * editor will indicate that tools have changed and prompt to refresh them.
+		 */
+		version?: string;
+
+		/**
+		 * @param label The human-readable name of the server.
+		 * @param uri The URI of the server.
+		 * @param headers Optional additional heads included with each request to the server.
+		 */
+		constructor(label: string, uri: Uri, headers?: Record<string, string>, version?: string);
+	}
+
+	/**
+	 * Definitions that describe different types of Model Context Protocol servers,
+	 * which can be returned from the {@link McpServerDefinitionProvider}.
+	 */
+	export type McpServerDefinition = McpStdioServerDefinition | McpHttpServerDefinition;
+
+	/**
+	 * A type that can provide Model Context Protocol server definitions. This
+	 * should be registered using {@link lm.registerMcpServerDefinitionProvider}
+	 * during extension activation.
+	 */
+	export interface McpServerDefinitionProvider<T extends McpServerDefinition = McpServerDefinition> {
+		/**
+		 * Optional event fired to signal that the set of available servers has changed.
+		 */
+		readonly onDidChangeMcpServerDefinitions?: Event<void>;
+
+		/**
+		 * Provides available MCP servers. The editor will call this method eagerly
+		 * to ensure the availability of servers for the language model, and so
+		 * extensions should not take actions which would require user
+		 * interaction, such as authentication.
+		 *
+		 * @param token A cancellation token.
+		 * @returns An array of MCP available MCP servers
+		 */
+		provideMcpServerDefinitions(token: CancellationToken): ProviderResult<T[]>;
+
+		/**
+		 * This function will be called when the editor needs to start a MCP server.
+		 * At this point, the extension may take any actions which may require user
+		 * interaction, such as authentication. Any non-`readonly` property of the
+		 * server may be modified, and the extension should return the resolved server.
+		 *
+		 * The extension may return undefined to indicate that the server
+		 * should not be started, or throw an error. If there is a pending tool
+		 * call, the editor will cancel it and return an error message to the
+		 * language model.
+		 *
+		 * @param server The MCP server to resolve
+		 * @param token A cancellation token.
+		 * @returns The resolved server or thenable that resolves to such. This may
+		 * be the given `server` definition with non-readonly properties filled in.
+		 */
+		resolveMcpServerDefinition?(server: T, token: CancellationToken): ProviderResult<T>;
+	}
+
 	/**
 	 * Namespace for language model related functionality.
 	 */
@@ -20291,6 +20424,34 @@ declare module 'vscode' {
 		 * @returns The result of the tool invocation.
 		 */
 		export function invokeTool(name: string, options: LanguageModelToolInvocationOptions<object>, token?: CancellationToken): Thenable<LanguageModelToolResult>;
+
+		/**
+		 * Registers a provider that publishes Model Context Protocol servers for the editor to
+		 * consume. This allows MCP servers to be dynamically provided to the editor in
+		 * addition to those the user creates in their configuration files.
+		 *
+		 * Before calling this method, extensions must register the `contributes.mcpServerDefinitionProviders`
+		 * extension point with the corresponding {@link id}, for example:
+		 *
+		 * ```js
+		 * 	"contributes": {
+		 * 		"mcpServerDefinitionProviders": [
+		 * 			{
+		 * 				"id": "cool-cloud-registry.mcp-servers",
+		 * 				"label": "Cool Cloud Registry",
+		 * 			}
+		 * 		]
+		 * 	}
+		 * ```
+		 *
+		 * When a new McpServerDefinitionProvider is available, the editor will present a 'refresh'
+		 * action to the user to discover new servers. To enable this flow, extensions should
+		 * call `registerMcpServerDefinitionProvider` during activation.
+		 * @param id The ID of the provider, which is unique to the extension.
+		 * @param provider The provider to register
+		 * @returns A disposable that unregisters the provider when disposed.
+		 */
+		export function registerMcpServerDefinitionProvider(id: string, provider: McpServerDefinitionProvider): Disposable;
 	}
 
 	/**