Track external tool calls

[roblourens]

No description provided.

[Copilot]

Pull request overview

This PR adds support for tracking external tool invocations from extensions in the chat system. It enables extensions to create live, in-progress tool invocations that can be updated and completed asynchronously, providing better visibility into tool execution status.

Changes:

• Introduced createExternal factory method and update/complete methods for external tool invocations
• Added new DTO type IChatExternalToolInvocationUpdateDto for streaming external tool invocation updates
• Implemented handling logic in mainThreadChatAgents2 to track and update external tool invocations

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
src/vs/workbench/contrib/chat/common/model/chatProgressTypes/chatToolInvocation.ts	Adds factory method, interface, and update/complete methods for external tool invocations
src/vs/workbench/api/common/extHostTypeConverters.ts	Converts ChatToolInvocationPart to either legacy serialized format or new update DTO based on isComplete field
src/vs/workbench/api/common/extHost.protocol.ts	Defines IChatExternalToolInvocationUpdateDto for external tool invocation updates
src/vs/workbench/api/browser/mainThreadChatAgents2.ts	Implements tracking map and handler for external tool invocation lifecycle

Comments suppressed due to low confidence (3)

src/vs/workbench/api/browser/mainThreadChatAgents2.ts:409

• When creating an external tool invocation that is already completed (isComplete: true on first push), it's added to the pending map and then immediately removed. This is inefficient - the invocation should only be added to _pendingExternalToolInvocations if it's not complete (isComplete: false).

		if (progress.isComplete) {
			// Already completed on first push
			invocation.completeExternalInvocation({
				pastTenseMessage: progress.pastTenseMessage,
				isError: progress.isError,
			});
		} else {
			// Track for future updates
			this._pendingExternalToolInvocations.set(progress.toolCallId, invocation);
		}

src/vs/workbench/api/browser/mainThreadChatAgents2.ts:388

• The check for existingInvocation and the early return on line 388 means that if an extension sends an update with isComplete: false after the invocation already exists, nothing is returned and no progress is added. However, if an invocation is created as complete on first push (line 400-405), it won't be in the pending map for any subsequent updates. This creates an inconsistent state where updating an already-completed invocation is silently ignored.

	private _handleExternalToolInvocationUpdate(progress: IChatExternalToolInvocationUpdateDto): ChatToolInvocation | undefined {
		const existingInvocation = this._pendingExternalToolInvocations.get(progress.toolCallId);

		if (existingInvocation) {
			if (progress.isComplete) {
				existingInvocation.completeExternalInvocation({
					pastTenseMessage: progress.pastTenseMessage,
					isError: progress.isError,
				});
				this._pendingExternalToolInvocations.delete(progress.toolCallId);
			} else {
				existingInvocation.updateExternalInvocation({
					invocationMessage: progress.invocationMessage,
					pastTenseMessage: progress.pastTenseMessage,
				});
			}
			return undefined;

src/vs/workbench/api/browser/mainThreadChatAgents2.ts:412

• The new external tool invocation functionality lacks test coverage. Consider adding tests for the following scenarios: (1) creating and completing external tool invocations, (2) updating in-progress invocations, (3) handling duplicate toolCallIds, (4) memory cleanup when requests complete, and (5) error state propagation. The existing test suite at src/vs/workbench/contrib/chat/test/browser/tools/languageModelToolsService.test.ts provides a good pattern to follow.

	/**
	 * Handle external tool invocation updates from extensions.
	 * Returns the invocation if it's new and should be added to progress, otherwise undefined.
	 */
	private _handleExternalToolInvocationUpdate(progress: IChatExternalToolInvocationUpdateDto): ChatToolInvocation | undefined {
		const existingInvocation = this._pendingExternalToolInvocations.get(progress.toolCallId);

		if (existingInvocation) {
			if (progress.isComplete) {
				existingInvocation.completeExternalInvocation({
					pastTenseMessage: progress.pastTenseMessage,
					isError: progress.isError,
				});
				this._pendingExternalToolInvocations.delete(progress.toolCallId);
			} else {
				existingInvocation.updateExternalInvocation({
					invocationMessage: progress.invocationMessage,
					pastTenseMessage: progress.pastTenseMessage,
				});
			}
			return undefined;
		}

		// Create a new external tool invocation
		const invocation = ChatToolInvocation.createExternal({
			toolCallId: progress.toolCallId,
			toolName: progress.toolName,
			invocationMessage: progress.invocationMessage,
			pastTenseMessage: progress.pastTenseMessage,
			toolSpecificData: progress.toolSpecificData as IPreparedToolInvocation['toolSpecificData'],
		});

		if (progress.isComplete) {
			// Already completed on first push
			invocation.completeExternalInvocation({
				pastTenseMessage: progress.pastTenseMessage,
				isError: progress.isError,
			});
		} else {
			// Track for future updates
			this._pendingExternalToolInvocations.set(progress.toolCallId, invocation);
		}

		return invocation;
	}