Merge origin/main into automations new chat input migration

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot-Session: 83b4f23f-9ae8-4cb3-be91-f383660edc25

Author: benvillalobos

.github/skills/agent-host-chat-contributions/SKILL.md

@@ -4024,6 +4024,15 @@
             ],
             "description": "%github.copilot.config.gemini35FlashReducedToolUsePrompt.enabled%"
           },
+          "github.copilot.chat.geminiFlashPromptAdditions.enabled": {
+            "type": "boolean",
+            "default": false,
+            "tags": [
+              "experimental",
+              "onExp"
+            ],
+            "description": "%github.copilot.config.geminiFlashPromptAdditions.enabled%"
+          },
           "github.copilot.chat.anthropic.contextEditing.mode": {
             "type": "string",
             "default": "off",

extensions/copilot/package.json

@@ -163,6 +163,7 @@
 	"github.copilot.config.alternateGptPrompt.enabled": "Enables an experimental alternate prompt for GPT models instead of the default prompt.",
 	"github.copilot.config.alternateGeminiModelFPrompt.enabled": "Enables an experimental alternate prompt for Gemini Model F instead of the default prompt.",
 	"github.copilot.config.gemini35FlashReducedToolUsePrompt.enabled": "Enables an experimental prompt for Gemini 3.5 Flash that instructs the model to minimize tool calls to reduce token usage.",
+	"github.copilot.config.geminiFlashPromptAdditions.enabled": "Enables experimental additional prompt guidance for Gemini Flash 3.6 and 3.7 models.",
 	"github.copilot.config.gpt5CodexAlternatePrompt": "Specifies an experimental alternate prompt to use for the GPT-5-Codex model.",
 	"github.copilot.command.fixTestFailure": "Fix Test Failure",
 	"copilot.description": "Ask or edit in context",

extensions/copilot/package.nls.json

@@ -228,6 +228,25 @@ const OPEN_PULL_REQUEST_COMMAND_ID = 'github.copilot.chat.cloudSessions.openPull
 const CLEAR_CACHES_COMMAND_ID = 'github.copilot.chat.cloudSessions.clearCaches';
 const CREATE_PULL_REQUEST_FOR_TASK_COMMAND_ID = 'github.copilot.chat.cloudSessions.createPullRequestForTask';
 const OPEN_PULL_REQUEST_FOR_TASK_COMMAND_ID = 'github.copilot.chat.cloudSessions.openPullRequestForTask';
+
+export function parseGitHubContextUrl(value: string, kind: 'issue' | 'pullRequest'): { readonly repoId: string; readonly url: string; readonly label: string } | undefined {
+	const match = /^https:\/\/(?:www\.)?github\.com\/(?<owner>[^/?#]+)\/(?<repository>[^/?#]+)\/(?<resource>issues|pull)\/(?<number>[1-9]\d*)\/?(?:[?#].*)?$/i.exec(value.trim());
+	if (!match?.groups) {
+		return undefined;
+	}
+	const resource = match.groups.resource.toLowerCase();
+	if ((resource === 'issues') !== (kind === 'issue')) {
+		return undefined;
+	}
+
+	const repoId = `${match.groups.owner}/${match.groups.repository}`;
+	return {
+		repoId,
+		url: `https://github.com/${repoId}/${resource}/${match.groups.number}`,
+		label: `${repoId}#${match.groups.number}`,
+	};
+}
+
 /** Context key gating the chat-input "Create pull request" toolbar action: true while the viewed cloud task is settled and has no PR yet. */
 const CAN_CREATE_PULL_REQUEST_CONTEXT_KEY = 'github.copilot.chat.cloudTaskCanCreatePullRequest';
 /** Context key gating the chat-input "Open pull request" toolbar action: true once the viewed cloud task has a pull request. */
@@ -706,6 +725,18 @@ export class CopilotCloudSessionsProvider extends Disposable implements vscode.C
 						clearTimeout(searchTimeout);
 					}
 					const query = value.trim();
+					const pastedSelection = parseGitHubContextUrl(query, kind);
+					if (pastedSelection) {
+						searchGeneration++;
+						quickPick.busy = false;
+						quickPick.items = [{
+							label: pastedSelection.label,
+							description: pastedSelection.repoId,
+							alwaysShow: true,
+							selection: pastedSelection,
+						}];
+						return;
+					}
 					if (query.length < 2) {
 						if (query.length === 0) {
 							void search('', ++searchGeneration);

extensions/copilot/src/extension/chatSessions/vscode-node/copilotCloudSessionsProvider.ts

@@ -12,7 +12,7 @@ import { mock } from '../../../../util/common/test/simpleMock';
 import { ChatRequestTurn2, ChatResponseMarkdownPart, ChatResponseTurn2, ChatToolInvocationPart } from '../../../../vscodeTypes';
 import { ITaskApiClient, ListTaskEventsOptions, ListTasksOptions } from '../../common/taskApiTypes';
 import { ChatSessionContentBuilder, extractTaskErrorDetail, formatTaskStoppedMessage } from '../copilotCloudSessionContentBuilder';
-import { formatNewSessionContextReference, getCloudSessionItemMetadata, getCloudSessionResources, normalizeInitialSessionOptions, taskStateToChatSessionStatus } from '../copilotCloudSessionsProvider';
+import { formatNewSessionContextReference, getCloudSessionItemMetadata, getCloudSessionResources, normalizeInitialSessionOptions, parseGitHubContextUrl, taskStateToChatSessionStatus } from '../copilotCloudSessionsProvider';
 import { TaskApiBackend, parseRepoFromTaskUrl, isCloudCodingAgentTask } from '../taskApiBackend';
 import { isActiveTaskState, isFailedTaskState } from '../../vscode/copilotCodingAgentUtils';
 import { NullCloudBackendInstrumentation } from '../cloudBackendTelemetry';
@@ -60,6 +60,28 @@ describe('copilotCloudSessionsProvider helpers', () => {
 		]);
 	});
 
+	it('parses pasted GitHub issue and pull request URLs for the matching picker', () => {
+		expect({
+			issue: parseGitHubContextUrl(' https://github.com/microsoft/vscode/ISSUES/333149#issuecomment-1 ', 'issue'),
+			pullRequest: parseGitHubContextUrl('https://www.github.com/microsoft/vscode/pull/333149/', 'pullRequest'),
+			wrongPicker: parseGitHubContextUrl('https://github.com/microsoft/vscode/pull/333149', 'issue'),
+			unrelated: parseGitHubContextUrl('https://example.com/microsoft/vscode/issues/333149', 'issue'),
+		}).toEqual({
+			issue: {
+				repoId: 'microsoft/vscode',
+				url: 'https://github.com/microsoft/vscode/issues/333149',
+				label: 'microsoft/vscode#333149',
+			},
+			pullRequest: {
+				repoId: 'microsoft/vscode',
+				url: 'https://github.com/microsoft/vscode/pull/333149',
+				label: 'microsoft/vscode#333149',
+			},
+			wrongPicker: undefined,
+			unrelated: undefined,
+		});
+	});
+
 	it('coerces object-shaped initialSessionOptions into option entries', () => {
 		const logService = new RecordingLogService();
 		const sessionResource = vscode.Uri.parse('copilot-cloud-agent:/1');

extensions/copilot/src/extension/chatSessions/vscode-node/test/copilotCloudSessionsProvider.spec.ts

@@ -9,6 +9,7 @@ import { ConfigKey, IConfigurationService } from '../../../platform/configuratio
 import { IEnvService } from '../../../platform/env/common/envService';
 import { IVSCodeExtensionContext } from '../../../platform/extContext/common/extensionContext';
 import { InlineEditRequestLogContext } from '../../../platform/inlineEdits/common/inlineEditLogContext';
+import { IInlineEditsModelService } from '../../../platform/inlineEdits/common/inlineEditsModelService';
 import { ObservableGit } from '../../../platform/inlineEdits/common/observableGit';
 import { NesHistoryContextProvider } from '../../../platform/inlineEdits/common/workspaceEditTracker/nesHistoryContextProvider';
 import { ILogService } from '../../../platform/log/common/logService';
@@ -63,6 +64,9 @@ export class InlineEditProviderFeature {
 	private readonly _yieldToCopilot = this._configurationService.getExperimentBasedConfigObservable(ConfigKey.TeamInternal.InlineEditsYieldToCopilot, this._expService);
 	private readonly _excludedProviders = this._configurationService.getExperimentBasedConfigObservable(ConfigKey.TeamInternal.InlineEditsExcludedProviders, this._expService).map(v => v ? v.split(',').map(v => v.trim()).filter(v => v !== '') : []);
 	private readonly _copilotToken = observableFromEvent(this, this._authenticationService.onDidCopilotTokenChange, () => this._authenticationService.copilotToken);
+	// Read reactively: on a fetched `/models` deployment this resolves async, so a brief cold-start
+	// window can emit completions until `onModelListUpdated` fires and re-registers with the excludes.
+	private readonly _supportsUnifiedCompletions = observableFromEvent(this, this._modelService.onModelListUpdated, () => this._modelService.selectedModelConfiguration().supportsUnifiedCompletions ?? false);
 
 	public readonly inlineEditsEnabled = derived(this, (reader) => {
 		const copilotToken = this._copilotToken.read(reader);
@@ -92,6 +96,7 @@ export class InlineEditProviderFeature {
 		@IExperimentationService private readonly _expService: IExperimentationService,
 		@IEnvService private readonly _envService: IEnvService,
 		@IInstantiationService private readonly _instantiationService: IInstantiationService,
+		@IInlineEditsModelService private readonly _modelService: IInlineEditsModelService,
 	) {
 	}
 
@@ -158,8 +163,11 @@ export class InlineEditProviderFeature {
 			const provider = this._instantiationService.createInstance(InlineCompletionProviderImpl, model, logger, logContextRecorder, inlineEditDebugComponent, telemetrySender, expectedEditCaptureController);
 
 			const unificationStateValue = unificationState.read(reader);
+			// Unify when the selected model's strategy bakes in `supportsUnifiedCompletions`, or when the
+			// core deployment/ExP `modelUnification` toggle is set.
+			const modelUnification = this._supportsUnifiedCompletions.read(reader) || (unificationStateValue?.modelUnification ?? false);
 			let excludes = this._excludedProviders.read(reader);
-			if (unificationStateValue?.modelUnification) {
+			if (modelUnification) {
 				excludes = excludes.slice(0);
 				if (!excludes.includes('completions')) {
 					excludes.push('completions');

extensions/copilot/src/extension/inlineEdits/vscode-node/inlineEditProviderFeature.ts

@@ -44,6 +44,14 @@ export class DefaultGeminiAgentPrompt extends PromptElement<DefaultAgentPromptPr
 			&& !isExcludedGeminiFamily
 			&& this.configurationService.getExperimentBasedConfig(ConfigKey.EnableGemini3ReducedToolUsePrompt, this.experimentationService);
 
+		// Experiment to study additional Gemini Flash 3.6/3.7 prompt guidance on the metrics.
+		const isGeminiFlash36Or37 = !!modelFamily && (
+			modelFamily.includes('gemini-3.6-flash')
+			|| modelFamily.includes('gemini-3.7-flash')
+		);
+		const enableFlashPromptAdditions = isGeminiFlash36Or37
+			&& this.configurationService.getExperimentBasedConfig(ConfigKey.EnableGeminiFlashPromptAdditions, this.experimentationService);
+
 		return <InstructionMessage>
 			<Tag name='instructions'>
 				You are a highly sophisticated automated coding agent with expert-level knowledge across many different programming languages and frameworks.<br />
@@ -55,6 +63,7 @@ export class DefaultGeminiAgentPrompt extends PromptElement<DefaultAgentPromptPr
 					? <>Tool calls to read files or search are expensive. Minimize their use by solving tasks in the fewest steps and tool calls possible.<br /></>
 					: <>If you aren't sure which tool is relevant, you can call multiple tools. You can call tools repeatedly to take actions or gather as much context as needed until you have completed the task fully. Don't give up unless you are sure the request cannot be fulfilled with the tools you have. It's YOUR RESPONSIBILITY to make sure that you have done all you can to collect necessary context.<br /></>}
 				When reading files, prefer reading large meaningful chunks rather than consecutive small sections to minimize tool calls and gain better context.<br />
+				{enableFlashPromptAdditions && <>**Read ast/definitions first**: When inspecting a new codebase, prioritize reading configuration files (e.g. package.json, tsconfig.json) or directory listings before searching for source files blindly.<br /></>}
 				Don't make assumptions about the situation- gather context first, then perform the task or answer the question.<br />
 				{!this.props.codesearchMode && <>Think creatively and explore the workspace in order to make a complete fix.<br /></>}
 				Don't repeat yourself after a tool call, pick up where you left off.<br />
@@ -75,6 +84,8 @@ export class DefaultGeminiAgentPrompt extends PromptElement<DefaultAgentPromptPr
 				{tools[ToolName.FindTextInFiles] && <>You can use the {ToolName.FindTextInFiles} to get an overview of a file by searching for a string within that one file, instead of using {ToolName.ReadFile} many times.<br /></>}
 				{tools[ToolName.Codebase] && <>If you don't know exactly the string or filename pattern you're looking for, use {ToolName.Codebase} to do a semantic search across the workspace.<br /></>}
 				{tools[ToolName.CoreRunInTerminal] && <>Don't call the {ToolName.CoreRunInTerminal} tool multiple times in parallel. Instead, run one command and wait for the output before running the next command.<br /></>}
+				{enableFlashPromptAdditions && tools[ToolName.CoreRunInTerminal] && <>**Tool Batching**: Combine terminal execution steps. If you need to verify multiple files or run multiple tests, chain them into a single terminal command (e.g., pytest tests/a.py tests/b.py).<br /></>}
+				{enableFlashPromptAdditions && tools[ToolName.FindTextInFiles] && <>**Search Precision**: Refine {ToolName.FindTextInFiles} patterns to target exact definitions rather than running broad, high-volume keyword searches that clutter the context window.<br /></>}
 				When invoking a tool that takes a file path, always use the absolute file path. If the file has a scheme like untitled: or vscode-userdata:, then use a URI with the scheme.<br />
 				{tools[ToolName.CoreRunInTerminal] && <>NEVER try to edit a file by running terminal commands unless the user specifically asks for it.<br /></>}
 				{!tools.hasSomeEditTool && <>You don't currently have any tools available for editing files. If the user asks you to edit a file, you can ask the user to enable editing tools or print a codeblock with the suggested changes.<br /></>}

extensions/copilot/src/extension/prompts/node/agent/geminiPrompts.tsx

@@ -18,6 +18,7 @@ import { createTextDocumentData } from '../../../../../util/common/test/shims/te
 import { URI } from '../../../../../util/vs/base/common/uri';
 import { SyncDescriptor } from '../../../../../util/vs/platform/instantiation/common/descriptors';
 import { IInstantiationService } from '../../../../../util/vs/platform/instantiation/common/instantiation';
+import type { LanguageModelToolInformation } from 'vscode';
 import { ChatRequestEditedFileEventKind, LanguageModelTextPart, LanguageModelToolResult } from '../../../../../vscodeTypes';
 import { addCacheBreakpoints } from '../../../../intents/node/cacheBreakpoints';
 import { ChatVariablesCollection } from '../../../../prompt/common/chatVariablesCollection';
@@ -385,3 +386,90 @@ testFamilies.forEach(family => {
 		});
 	});
 });
+
+suite('AgentPrompt - Gemini Flash prompt additions experiment', () => {
+	let accessor: ITestingServicesAccessor;
+
+	beforeAll(() => {
+		const services = createExtensionUnitTestingServices();
+		services.define(IWorkspaceService, new SyncDescriptor(TestWorkspaceService, [[URI.file('/workspace')]]));
+		services.define(IChatMLFetcher, new StaticChatMLFetcher([]));
+		accessor = services.createTestingAccessor();
+	});
+
+	afterAll(() => {
+		accessor.dispose();
+	});
+
+	async function renderForFamily(family: string, includeToolSpecificTools = true): Promise<string> {
+		const instaService = accessor.get(IInstantiationService);
+		const endpoint = instaService.createInstance(MockEndpoint, family);
+		const toolsService = accessor.get(IToolsService);
+		const turn = new Turn('turnId', { type: 'user', message: 'hello' });
+		const conversation = new Conversation('sessionId', [turn]);
+		const customizations = await PromptRegistry.resolveAllCustomizations(instaService, endpoint);
+		const syntheticTool = (name: ToolName): LanguageModelToolInformation => ({
+			name,
+			description: '',
+			inputSchema: undefined,
+			tags: [],
+			source: undefined,
+		});
+		const availableTools = includeToolSpecificTools
+			? [...toolsService.tools, syntheticTool(ToolName.CoreRunInTerminal), syntheticTool(ToolName.FindTextInFiles)]
+			: toolsService.tools.filter(t => t.name !== ToolName.CoreRunInTerminal && t.name !== ToolName.FindTextInFiles);
+		const props: AgentPromptProps = {
+			priority: 1,
+			endpoint,
+			location: ChatLocation.Panel,
+			promptContext: {
+				chatVariables: new ChatVariablesCollection(),
+				history: [],
+				query: 'hello',
+				conversation,
+				tools: {
+					availableTools,
+					toolInvocationToken: null as never,
+					toolReferences: [],
+				},
+			},
+			customizations,
+		};
+		const renderer = PromptRenderer.create(instaService, endpoint, AgentPrompt, props);
+		const r = await renderer.render();
+		return r.messages.map(m => messageToMarkdown(m)).join('\n\n');
+	}
+
+	function assertAdditions(rendered: string, expected: { readAst: boolean; toolBatching: boolean; searchPrecision: boolean }) {
+		expect({
+			readAst: rendered.includes('Read ast/definitions first'),
+			toolBatching: rendered.includes('**Tool Batching**'),
+			searchPrecision: rendered.includes('**Search Precision**'),
+		}).toEqual(expected);
+	}
+
+	test('additions appear for Gemini Flash 3.6 when experiment is enabled', async () => {
+		accessor.get(IConfigurationService).setConfig(ConfigKey.EnableGeminiFlashPromptAdditions, true);
+		assertAdditions(await renderForFamily('gemini-3.6-flash'), { readAst: true, toolBatching: true, searchPrecision: true });
+	});
+
+	test('additions appear for Gemini Flash 3.7 when experiment is enabled', async () => {
+		accessor.get(IConfigurationService).setConfig(ConfigKey.EnableGeminiFlashPromptAdditions, true);
+		assertAdditions(await renderForFamily('gemini-3.7-flash'), { readAst: true, toolBatching: true, searchPrecision: true });
+	});
+
+	test('tool-specific additions are gated on tool availability', async () => {
+		accessor.get(IConfigurationService).setConfig(ConfigKey.EnableGeminiFlashPromptAdditions, true);
+		assertAdditions(await renderForFamily('gemini-3.6-flash', /* includeToolSpecificTools */ false), { readAst: true, toolBatching: false, searchPrecision: false });
+	});
+
+	test('additions are omitted for Gemini Flash 3.6 when experiment is disabled', async () => {
+		accessor.get(IConfigurationService).setConfig(ConfigKey.EnableGeminiFlashPromptAdditions, false);
+		assertAdditions(await renderForFamily('gemini-3.6-flash'), { readAst: false, toolBatching: false, searchPrecision: false });
+	});
+
+	test('additions are omitted for other Gemini families even when experiment is enabled', async () => {
+		accessor.get(IConfigurationService).setConfig(ConfigKey.EnableGeminiFlashPromptAdditions, true);
+		assertAdditions(await renderForFamily('gemini-2.0-flash'), { readAst: false, toolBatching: false, searchPrecision: false });
+	});
+});

extensions/copilot/src/extension/prompts/node/agent/test/agentPrompt.spec.tsx

@@ -1072,6 +1072,7 @@ export namespace ConfigKey {
 	export const EnableAlternateGptPrompt = defineSetting<boolean>('chat.alternateGptPrompt.enabled', ConfigType.ExperimentBased, false);
 	export const EnableAlternateGeminiModelFPrompt = defineSetting<boolean>('chat.alternateGeminiModelFPrompt.enabled', ConfigType.ExperimentBased, false);
 	export const EnableGemini3ReducedToolUsePrompt = defineSetting<boolean>('chat.gemini35FlashReducedToolUsePrompt.enabled', ConfigType.ExperimentBased, true);
+	export const EnableGeminiFlashPromptAdditions = defineSetting<boolean>('chat.geminiFlashPromptAdditions.enabled', ConfigType.ExperimentBased, false);
 
 	export const EnableOrganizationCustomAgents = defineSetting<boolean>('chat.organizationCustomAgents.enabled', ConfigType.Simple, true);
 	export const EnableOrganizationInstructions = defineSetting<boolean>('chat.organizationInstructions.enabled', ConfigType.Simple, true);