Fix web_fetch tool showing empty content when expanded

- Add formatWebFetchInvocation() in copilotCLITools.ts to show URL in invocationMessage/pastTenseMessage
- Add web_fetch handling in copilotToolDisplay.ts getInvocationMessage/getPastTenseMessage
- Add test for web_fetch invocation formatting

Agent-Logs-Url: https://github.com/microsoft/vscode/sessions/26446ad4-2529-41d2-b8c5-a3b073ef2a4b

Co-authored-by: DonJayamanne <1948812+DonJayamanne@users.noreply.github.com>

Author: Copilot

extensions/copilot/src/extension/chatSessions/copilotcli/common/copilotCLITools.ts

@@ -1061,7 +1061,7 @@ const ToolFriendlyNameAndHandlers: { [K in ToolCall['toolName']]: [title: string
 	'report_intent': [l10n.t('Report Intent'), emptyInvocation, genericToolInvocationCompleted],
 	'think': [l10n.t('Thinking'), emptyInvocation, genericToolInvocationCompleted],
 	'report_progress': [l10n.t('Progress update'), formatProgressToolInvocation, genericToolInvocationCompleted],
-	'web_fetch': [l10n.t('Fetch Web Content'), emptyInvocation, genericToolInvocationCompleted],
+	'web_fetch': [l10n.t('Fetch Web Content'), formatWebFetchInvocation, genericToolInvocationCompleted],
 	'web_search': [l10n.t('Web Search'), emptyInvocation, genericToolInvocationCompleted],
 	'update_todo': [l10n.t('Update Todo'), formatUpdateTodoInvocation, formatUpdateTodoInvocationCompleted],
 	'show_file': [l10n.t('Show File'), formatShowFileInvocation, genericToolInvocationCompleted],
@@ -1101,6 +1101,15 @@ function formatProgressToolInvocation(invocation: ChatToolInvocationPart, toolCa
 
 
 
+function formatWebFetchInvocation(invocation: ChatToolInvocationPart, toolCall: WebFetchTool): void {
+	const url = toolCall.arguments.url;
+	if (url) {
+		const displayUrl = url.length > 80 ? url.substring(0, 77) + '...' : url;
+		invocation.invocationMessage = l10n.t("Fetching {0}", displayUrl);
+		invocation.pastTenseMessage = l10n.t("Fetched {0}", displayUrl);
+	}
+}
+
 function formatViewToolInvocation(invocation: ChatToolInvocationPart, toolCall: ViewTool): void {
 	const args = toolCall.arguments;
 

extensions/copilot/src/extension/chatSessions/copilotcli/common/test/copilotCLITools.spec.ts

@@ -563,6 +563,11 @@ describe('CopilotCLITools', () => {
 			const part = createCopilotCLIToolInvocation({ toolName: 'codeql_checker', toolCallId: 'cq1', arguments: {} });
 			expect(part).toBeInstanceOf(ChatToolInvocationPart);
 		});
+		it('formats web_fetch invocation with url', () => {
+			const part = createCopilotCLIToolInvocation({ toolName: 'web_fetch', toolCallId: 'wf1', arguments: { url: 'https://example.com/page' } });
+			expect(part).toBeInstanceOf(ChatToolInvocationPart);
+			expect(getInvocationMessageText(part as ChatToolInvocationPart)).toContain('https://example.com/page');
+		});
 	});
 
 	describe('process tool execution lifecycle', () => {

src/vs/platform/agentHost/node/copilot/copilotToolDisplay.ts

@@ -80,6 +80,11 @@ interface ICopilotGlobToolArgs {
 	path?: string;
 }
 
+/** Parameters for the `web_fetch` tool. */
+interface ICopilotWebFetchToolArgs {
+	url: string;
+}
+
 /** Set of tool names that perform file edits. */
 const EDIT_TOOL_NAMES: ReadonlySet<string> = new Set([
 	CopilotToolName.Edit,
@@ -245,6 +250,13 @@ export function getInvocationMessage(toolName: string, displayName: string, para
 			}
 			return localize('toolInvoke.glob', "Finding files");
 		}
+		case CopilotToolName.WebFetch: {
+			const args = parameters as ICopilotWebFetchToolArgs | undefined;
+			if (args?.url) {
+				return md(localize('toolInvoke.webFetch', "Fetching {0}", appendEscapedMarkdownInlineCode(truncate(args.url, 80))));
+			}
+			return localize('toolInvoke.webFetchGeneric', "Fetching web content");
+		}
 		default:
 			return localize('toolInvoke.generic', "Using \"{0}\"", displayName);
 	}
@@ -300,6 +312,13 @@ export function getPastTenseMessage(toolName: string, displayName: string, param
 			}
 			return localize('toolComplete.glob', "Found files");
 		}
+		case CopilotToolName.WebFetch: {
+			const args = parameters as ICopilotWebFetchToolArgs | undefined;
+			if (args?.url) {
+				return md(localize('toolComplete.webFetch', "Fetched {0}", appendEscapedMarkdownInlineCode(truncate(args.url, 80))));
+			}
+			return localize('toolComplete.webFetchGeneric', "Fetched web content");
+		}
 		default:
 			return localize('toolComplete.generic', "Used \"{0}\"", displayName);
 	}