Finalize ChatRequest#model (#231811)

* Finalize ChatRequest#model
Fix #230844

* Register model to fix tests

extensions/vscode-api-tests/src/singlefolder-tests/chat.test.ts

@@ -5,7 +5,7 @@
 
 import * as assert from 'assert';
 import 'mocha';
-import { ChatContext, ChatRequest, ChatResult, ChatVariableLevel, Disposable, Event, EventEmitter, chat, commands } from 'vscode';
+import { ChatContext, ChatRequest, ChatResult, ChatVariableLevel, Disposable, Event, EventEmitter, chat, commands, lm } from 'vscode';
 import { DeferredPromise, asPromise, assertNoRpc, closeAllEditors, delay, disposeAll } from '../utils';
 
 suite('chat', () => {
@@ -13,6 +13,25 @@ suite('chat', () => {
 	let disposables: Disposable[] = [];
 	setup(() => {
 		disposables = [];
+
+		// Register a dummy default model which is required for a participant request to go through
+		disposables.push(lm.registerChatModelProvider('test-lm', {
+			async provideLanguageModelResponse(_messages, _options, _extensionId, _progress, _token) {
+				return undefined;
+			},
+			async provideTokenCount(_text, _token) {
+				return 1;
+			},
+		}, {
+			name: 'test-lm',
+			version: '1.0.0',
+			family: 'test',
+			vendor: 'test-lm-vendor',
+			maxInputTokens: 100,
+			maxOutputTokens: 100,
+			isDefault: true,
+			isUserSelectable: true
+		}));
 	});
 
 	teardown(async function () {

src/vs/workbench/api/common/extHostChatAgents2.ts

@@ -369,10 +369,8 @@ export class ExtHostChatAgents2 extends Disposable implements ExtHostChatAgentsS
 			return undefined;
 		}
 
-		const extRequest = typeConvert.ChatAgentRequest.to(request, location);
-		if (request.userSelectedModelId && isProposedApiEnabled(detector.extension, 'chatParticipantAdditions')) {
-			extRequest.userSelectedModel = await this._languageModels.getLanguageModelByIdentifier(detector.extension, request.userSelectedModelId);
-		}
+		const model = await this.getModelForRequest(request, detector.extension);
+		const extRequest = typeConvert.ChatAgentRequest.to(request, location, model);
 
 		return detector.provider.provideParticipantDetection(
 			extRequest,
@@ -405,6 +403,21 @@ export class ExtHostChatAgents2 extends Disposable implements ExtHostChatAgentsS
 		return { request, location, history: convertedHistory };
 	}
 
+	private async getModelForRequest(request: IChatAgentRequest, extension: IExtensionDescription): Promise<vscode.LanguageModelChat> {
+		let model: vscode.LanguageModelChat | undefined;
+		if (request.userSelectedModelId) {
+			model = await this._languageModels.getLanguageModelByIdentifier(extension, request.userSelectedModelId);
+		}
+		if (!model) {
+			model = await this._languageModels.getDefaultLanguageModel(extension);
+			if (!model) {
+				throw new Error('Language model unavailable');
+			}
+		}
+
+		return model;
+	}
+
 	async $invokeAgent(handle: number, requestDto: Dto<IChatAgentRequest>, context: { history: IChatAgentHistoryEntryDto[] }, token: CancellationToken): Promise<IChatAgentResult | undefined> {
 		const agent = this._agents.get(handle);
 		if (!agent) {
@@ -425,10 +438,8 @@ export class ExtHostChatAgents2 extends Disposable implements ExtHostChatAgentsS
 
 			stream = new ChatAgentResponseStream(agent.extension, request, this._proxy, this._commands.converter, sessionDisposables);
 
-			const extRequest = typeConvert.ChatAgentRequest.to(request, location);
-			if (request.userSelectedModelId && isProposedApiEnabled(agent.extension, 'chatParticipantAdditions')) {
-				extRequest.userSelectedModel = await this._languageModels.getLanguageModelByIdentifier(agent.extension, request.userSelectedModelId);
-			}
+			const model = await this.getModelForRequest(request, agent.extension);
+			const extRequest = typeConvert.ChatAgentRequest.to(request, location, model);
 
 			const task = agent.invoke(
 				extRequest,

src/vs/workbench/api/common/extHostLanguageModels.ts

@@ -292,6 +292,15 @@ export class ExtHostLanguageModels implements ExtHostLanguageModelsShape {
 		this._onDidChangeProviders.fire(undefined);
 	}
 
+	async getDefaultLanguageModel(extension: IExtensionDescription): Promise<vscode.LanguageModelChat | undefined> {
+		const defaultModelId = Iterable.find(this._allLanguageModelData.entries(), ([, value]) => !!value.metadata.isDefault)?.[0];
+		if (!defaultModelId) {
+			return;
+		}
+
+		return this.getLanguageModelByIdentifier(extension, defaultModelId);
+	}
+
 	async getLanguageModelByIdentifier(extension: IExtensionDescription, identifier: string): Promise<vscode.LanguageModelChat | undefined> {
 
 		const data = this._allLanguageModelData.get(identifier);

src/vs/workbench/api/common/extHostTypeConverters.ts

@@ -2765,7 +2765,7 @@ export namespace ChatResponsePart {
 }
 
 export namespace ChatAgentRequest {
-	export function to(request: IChatAgentRequest, location2: vscode.ChatRequestEditorData | vscode.ChatRequestNotebookData | undefined): vscode.ChatRequest {
+	export function to(request: IChatAgentRequest, location2: vscode.ChatRequestEditorData | vscode.ChatRequestNotebookData | undefined, model: vscode.LanguageModelChat): vscode.ChatRequest {
 		const toolReferences = request.variables.variables.filter(v => v.isTool);
 		const variableReferences = request.variables.variables.filter(v => !v.isTool);
 		return {
@@ -2780,7 +2780,8 @@ export namespace ChatAgentRequest {
 			acceptedConfirmationData: request.acceptedConfirmationData,
 			rejectedConfirmationData: request.rejectedConfirmationData,
 			location2,
-			toolInvocationToken: Object.freeze({ sessionId: request.sessionId })
+			toolInvocationToken: Object.freeze({ sessionId: request.sessionId }),
+			model
 		};
 	}
 }

src/vscode-dts/vscode.d.ts

@@ -19086,6 +19086,12 @@ declare module 'vscode' {
 		 * string-manipulation of the prompt.
 		 */
 		readonly references: readonly ChatPromptReference[];
+
+		/**
+		 * This is the model that is currently selected in the UI. Extensions can use this or use {@link chat.selectChatModels} to
+		 * pick another model. Don't hold onto this past the lifetime of the request.
+		 */
+		readonly model: LanguageModelChat;
 	}
 
 	/**

src/vscode-dts/vscode.proposed.chatParticipantAdditions.d.ts

@@ -223,8 +223,6 @@ declare module 'vscode' {
 		 * The `data` for any confirmations that were rejected
 		 */
 		rejectedConfirmationData?: any[];
-
-		userSelectedModel?: LanguageModelChat;
 	}
 
 	// TODO@API fit this into the stream