Chat Agent Sample -> Chat Sample

fyi @roblourens

chat-sample/src/vscode.proposed.chatVariableResolver.d.ts

@@ -0,0 +1,52 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+declare module 'vscode' {
+
+	export namespace chat {
+
+		/**
+		 * Register a variable which can be used in a chat request to any participant.
+		 * @param name The name of the variable, to be used in the chat input as `#name`.
+		 * @param description A description of the variable for the chat input suggest widget.
+		 * @param resolver Will be called to provide the chat variable's value when it is used.
+		 */
+		export function registerChatVariableResolver(name: string, description: string, resolver: ChatVariableResolver): Disposable;
+	}
+
+	export interface ChatVariableValue {
+		/**
+		 * The detail level of this chat variable value. If possible, variable resolvers should try to offer shorter values that will consume fewer tokens in an LLM prompt.
+		 */
+		level: ChatVariableLevel;
+
+		/**
+		 * The variable's value, which can be included in an LLM prompt as-is, or the chat participant may decide to read the value and do something else with it.
+		 */
+		value: string | Uri;
+
+		/**
+		 * A description of this value, which could be provided to the LLM as a hint.
+		 */
+		description?: string;
+	}
+
+	export interface ChatVariableContext {
+		/**
+		 * The message entered by the user, which includes this variable.
+		 */
+		prompt: string;
+	}
+
+	export interface ChatVariableResolver {
+		/**
+		 * A callback to resolve the value of a chat variable.
+		 * @param name The name of the variable.
+		 * @param context Contextual information about this chat request.
+		 * @param token A cancellation token.
+		 */
+		resolve(name: string, context: ChatVariableContext, token: CancellationToken): ProviderResult<ChatVariableValue[]>;
+	}
+}