Support showing promo messages with no end date and no % discount (#329193)

* Support showing promo messages with no end date and no % discount

* Address PR feedback on promo message support

- Tighten promo JSDoc on the metadata contract, notification contribution,
  and helpers to match repository JSDoc limits
- Document the positive/zero/negative discount cases so message-only promos
  are not omitted by agent implementations
- Cover open-ended, message-only promos through the untyped _meta read and
  the CAPI billing normalization

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: edb3b42a-1bec-45f8-9453-51ad10583f06

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: edb3b42a-1bec-45f8-9453-51ad10583f06

extensions/copilot/src/platform/endpoint/common/endpointProvider.ts

@@ -105,7 +105,8 @@ export interface IModelTokenPrices {
 export interface IModelPromo {
 	id: string;
 	discount_percent: number;
-	ends_at: string;
+	/** ISO 8601 end date; absent for open-ended promotions. */
+	ends_at?: string;
 	message: string;
 }
 

extensions/copilot/src/platform/endpoint/node/chatEndpoint.ts

@@ -181,7 +181,7 @@ export class ChatEndpoint implements IChatEndpoint {
 	public readonly customModel?: CustomModel | undefined;
 	public readonly maxPromptImages?: number | undefined;
 	public readonly warningText?: Record<string, string> | undefined;
-	public readonly promo?: { id: string; discountPercent: number; endsAt: string; message: string } | undefined;
+	public readonly promo?: { id: string; discountPercent: number; endsAt?: string; message: string } | undefined;
 
 	private readonly _supportsStreaming: boolean;
 

extensions/copilot/src/platform/networking/common/networking.ts

@@ -342,7 +342,7 @@ export interface IChatEndpoint extends IEndpoint {
 	readonly isPremium?: boolean;
 	readonly degradationReason?: string;
 	readonly warningText?: Record<string, string>;
-	readonly promo?: { id: string; discountPercent: number; endsAt: string; message: string };
+	readonly promo?: { id: string; discountPercent: number; endsAt?: string; message: string };
 	readonly multiplier?: number;
 	readonly restrictedToSkus?: string[];
 	/**

src/vs/platform/agentHost/common/agentModelPricing.ts

@@ -39,11 +39,12 @@ export interface IAgentModelPricingMeta {
 	readonly category?: string;
 	/** Whole-number percentage discount (0-100) for the synthetic `auto` model; shown as a "{n}% discount" detail. */
 	readonly discountPercent?: number;
-	/** Promotional information when the model is experiencing a discount. */
+	/** Promotional information for the model. A `discountPercent` of `0` is a valid message-only promo. */
 	readonly promo?: {
 		readonly id: string;
 		readonly discountPercent: number;
-		readonly endsAt: string;
+		/** ISO 8601 end date; absent for open-ended promotions. */
+		readonly endsAt?: string;
 		readonly message: string;
 	};
 }
@@ -87,8 +88,13 @@ export function readAgentModelPricingMeta(model: IAgentModelInfo | SessionModelI
 	const rawPromo = meta.promo;
 	if (rawPromo && typeof rawPromo === 'object' && !Array.isArray(rawPromo)) {
 		const p = rawPromo as Record<string, unknown>;
-		if (typeof p.id === 'string' && typeof p.discountPercent === 'number' && typeof p.endsAt === 'string' && typeof p.message === 'string') {
-			result.promo = { id: p.id, discountPercent: p.discountPercent, endsAt: p.endsAt, message: p.message };
+		if (typeof p.id === 'string' && typeof p.discountPercent === 'number' && typeof p.message === 'string') {
+			result.promo = {
+				id: p.id,
+				discountPercent: p.discountPercent,
+				message: p.message,
+				...(typeof p.endsAt === 'string' ? { endsAt: p.endsAt } : {}),
+			};
 		}
 	}
 	return result;
@@ -175,8 +181,8 @@ function normalizePromo(billing: Record<string, unknown>): ICAPIModelBilling['pr
 		: typeof raw.ends_at === 'string' ? raw.ends_at
 			: undefined;
 	const message = typeof raw.message === 'string' ? raw.message : undefined;
-	if (id && typeof discountPercent === 'number' && endsAt && message) {
-		return { id, discountPercent, endsAt, message };
+	if (id && typeof discountPercent === 'number' && message) {
+		return { id, discountPercent, message, ...(endsAt ? { endsAt } : {}) };
 	}
 	return undefined;
 }
@@ -191,11 +197,12 @@ export interface ICAPIModelBilling {
 	readonly priceCategory?: string;
 	/** Whole-number percentage discount (0-100) for the synthetic `auto` model; rendered as a "{n}% discount" detail. */
 	readonly discountPercent?: number;
-	/** Promotional info when the model is experiencing a promotional discount. */
+	/** Promotional information for the model. A `discountPercent` of `0` is a valid message-only promo. */
 	readonly promo?: {
 		readonly id: string;
 		readonly discountPercent: number;
-		readonly endsAt: string;
+		/** ISO 8601 end date; absent for open-ended promotions. */
+		readonly endsAt?: string;
 		readonly message: string;
 	};
 	readonly tokenPrices?: {

src/vs/platform/agentHost/test/node/copilotAgent.test.ts

@@ -2129,6 +2129,26 @@ suite('CopilotAgent', () => {
 		}
 	});
 
+	test('models keep an open-ended, message-only promotion', async () => {
+		const agent = createTestAgent(disposables, {
+			copilotClient: new TestCopilotClient([], [{
+				id: 'claude-sonnet',
+				name: 'Claude Sonnet',
+				capabilities: { limits: { max_context_window_tokens: 200_000 } },
+				// No `endsAt` and a zero discount: the promo must survive normalization.
+				billing: { multiplier: 1, promo: { id: 'featured', discountPercent: 0, message: 'Now available' } },
+			}]),
+		});
+		try {
+			await agent.authenticate('https://api.github.com', 'token');
+			const models = await waitForState(agent.models, models => models.length > 0);
+
+			assert.deepStrictEqual(models[0]._meta?.promo, { id: 'featured', discountPercent: 0, message: 'Now available' });
+		} finally {
+			await disposeAgent(agent);
+		}
+	});
+
 	test('configSchema emits a thinkingLevel property when the model advertises reasoning efforts', async () => {
 		const agent = createTestAgent(disposables, {
 			copilotClient: new TestCopilotClient([], [{

src/vs/workbench/contrib/chat/browser/chatPromoNotification.ts

@@ -15,12 +15,8 @@ const PROMO_NOTIFICATION_ID = 'copilot.promoNotification';
 const DISMISSED_PROMOS_STORAGE_KEY = 'chat.dismissedPromoIds';
 
 /**
- * Watches for models with active promotions and surfaces a chat input
- * notification per harness (chat session type) the first time each promo
- * appears. Each notification is scoped to the session type of the model that
- * carries the promo, so a chat input only advertises a model it can actually
- * switch to. Dismissals are persisted by promo id so the same promo is never
- * shown again.
+ * Surfaces a model's promo as a chat input notification, scoped to the harness
+ * (chat session type) of the model that carries it. Dismissals are persisted by promo id.
  */
 export class ChatPromoNotificationContribution extends Disposable implements IWorkbenchContribution {
 
@@ -50,18 +46,17 @@ export class ChatPromoNotificationContribution extends Disposable implements IWo
 		const dismissed = this._getDismissedPromoIds();
 		const modelIds = this._languageModelsService.getLanguageModelIds();
 
-		// A promo can appear in several harnesses at once (e.g. the same model
-		// offered in the Local, Copilot, and Codex sessions). Bucket the first
-		// non-dismissed promo per harness (a model's `targetChatSessionType`,
-		// or the local pool when unset).
+		// Bucket one non-dismissed promo per harness (a model's `targetChatSessionType`,
+		// or the local pool when unset), preferring a discounted promo over a message-only one.
 		const promoByHarness = new Map<string, ILanguageModelChatMetadataAndIdentifier>();
 		for (const id of modelIds) {
 			const meta = this._languageModelsService.lookupLanguageModel(id);
-			if (!meta || !ILanguageModelChatMetadata.hasPromoDiscount(meta) || dismissed.has(meta.promo.id)) {
+			if (!meta || !ILanguageModelChatMetadata.hasPromoMessage(meta) || dismissed.has(meta.promo.id)) {
 				continue;
 			}
 			const harness = meta.targetChatSessionType ?? localChatSessionType;
-			if (!promoByHarness.has(harness)) {
+			const current = promoByHarness.get(harness);
+			if (!current || (!ILanguageModelChatMetadata.hasPromoDiscount(current.metadata) && ILanguageModelChatMetadata.hasPromoDiscount(meta))) {
 				promoByHarness.set(harness, { identifier: id, metadata: meta });
 			}
 		}
@@ -82,15 +77,12 @@ export class ChatPromoNotificationContribution extends Disposable implements IWo
 			}
 			this._shownNotifications.set(notificationId, { promoId: promo.id, modelIdentifier: model.identifier });
 
-			const endsAtDate = new Date(promo.endsAt);
-			const formattedDate = endsAtDate.toLocaleDateString(undefined, { year: 'numeric', month: 'long', day: 'numeric' });
-
 			this._chatInputNotificationService.setNotification({
 				id: notificationId,
 				telemetryId: promo.id,
 				severity: ChatInputNotificationSeverity.Info,
 				message: promo.message,
-				description: localize('chat.promo.endsAt', "Ends {0}.", formattedDate),
+				description: ILanguageModelChatMetadata.getPromoEndsAtLabel(promo.endsAt),
 				actions: [{
 					label: localize('chat.promo.tryModel', "Try {0}", model.metadata.name),
 					kind: ChatInputNotificationActionKind.SwitchToModel,

src/vs/workbench/contrib/chat/browser/widget/input/modelPicker/modelPickerHover.ts

@@ -78,9 +78,8 @@ export function getModelHoverContent(
 	if (promo) {
 		const promoContainer = dom.$('.chat-model-hover-promo-text');
 		promoContainer.appendChild(renderIcon(Codicon.info));
-		const endsAtDate = new Date(promo.endsAt);
-		const formattedDate = endsAtDate.toLocaleDateString(undefined, { year: 'numeric', month: 'long', day: 'numeric' });
-		const promoMessage = promo.message + ' ' + localize('chat.promo.endsAt', "Ends {0}.", formattedDate);
+		const endsAtLabel = ILanguageModelChatMetadata.getPromoEndsAtLabel(promo.endsAt);
+		const promoMessage = endsAtLabel ? promo.message + ' ' + endsAtLabel : promo.message;
 		const promoMd = new MarkdownString(promoMessage, { isTrusted: false, supportThemeIcons: true });
 		const rendered = disposables.add(renderMarkdown(promoMd, {
 			actionHandler: link => { void openerService.open(link, { allowCommands: false, fromUserGesture: true }); },

src/vs/workbench/contrib/chat/common/chatSessionsService.ts

@@ -86,7 +86,7 @@ export interface IChatSessionProviderOptionModelMetadata {
 	readonly promo?: {
 		readonly id: string;
 		readonly discountPercent: number;
-		readonly endsAt: string;
+		readonly endsAt?: string;
 		readonly message: string;
 	};
 	readonly maxInputTokens?: number;

src/vs/workbench/contrib/chat/common/languageModels.ts

@@ -322,13 +322,15 @@ export interface ILanguageModelChatMetadata {
 	 */
 	readonly warningText?: IStringDictionary<string>;
 	/**
-	 * Optional promotional information for this model. Positive discounts surface
-	 * promotional UI; non-positive discounts only feature the model in the picker.
+	 * Optional promotional information for this model. A positive `discountPercent`
+	 * surfaces the full promotional UI; `0` is a message-only promo that features the
+	 * model without a price change; a negative value is malformed and is ignored.
+	 * `endsAt` is optional — open-ended promos omit it and render no end date.
 	 */
 	readonly promo?: {
 		readonly id: string;
 		readonly discountPercent: number;
-		readonly endsAt: string;
+		readonly endsAt?: string;
 		readonly message: string;
 	};
 }
@@ -354,6 +356,24 @@ export namespace ILanguageModelChatMetadata {
 		return !!metadata.promo && metadata.promo.discountPercent > 0;
 	}
 
+	/** Whether the model has a promo message to surface, including message-only (0%) promos. */
+	export function hasPromoMessage(metadata: ILanguageModelChatMetadata): metadata is ILanguageModelChatMetadata & { readonly promo: NonNullable<ILanguageModelChatMetadata['promo']> } {
+		return !!metadata.promo && metadata.promo.discountPercent >= 0 && !!metadata.promo.message;
+	}
+
+	/** The localized "Ends {date}." sentence, or `undefined` for a missing or unparsable end date. */
+	export function getPromoEndsAtLabel(endsAt: string | undefined): string | undefined {
+		if (!endsAt) {
+			return undefined;
+		}
+		const endsAtDate = new Date(endsAt);
+		if (isNaN(endsAtDate.getTime())) {
+			return undefined;
+		}
+		const formattedDate = endsAtDate.toLocaleDateString(undefined, { year: 'numeric', month: 'long', day: 'numeric' });
+		return localize('chat.promo.endsAt', "Ends {0}.", formattedDate);
+	}
+
 	/**
 	 * Documentation link explaining how Auto model selection works.
 	 * NOTE: Also defined in extensions/copilot/src/extension/conversation/common/languageModelAccess.ts — keep in sync.

src/vs/workbench/contrib/chat/test/browser/agentSessions/agentHostLanguageModelProvider.test.ts

@@ -56,32 +56,50 @@ suite('AgentHostLanguageModelProvider', () => {
 
 	test('carries picker category, price category, and promo from model metadata', async () => {
 		const provider = createProvider();
-		provider.updateModels([makeModel('claude-sonnet', {
-			category: 'powerful',
-			priceCategory: 'medium',
-			promo: {
-				id: 'summer-sale',
-				discountPercent: 25,
-				endsAt: '2026-08-01T00:00:00Z',
-				message: 'Save on Claude Sonnet',
-			},
-		})]);
+		provider.updateModels([
+			makeModel('claude-sonnet', {
+				category: 'powerful',
+				priceCategory: 'medium',
+				promo: {
+					id: 'summer-sale',
+					discountPercent: 25,
+					endsAt: '2026-08-01T00:00:00Z',
+					message: 'Save on Claude Sonnet',
+				},
+			}),
+			// Open-ended, message-only promo: the untyped `_meta` read must keep it
+			// rather than drop the promo for the missing `endsAt` / zero discount.
+			makeModel('gpt-5', {
+				promo: {
+					id: 'featured',
+					discountPercent: 0,
+					message: 'Now available',
+				},
+			}),
+		]);
 
-		const metadata = (await provider.provideLanguageModelChatInfo(undefined, CancellationToken.None))[0].metadata;
-		assert.deepStrictEqual({
-			category: metadata.category,
-			priceCategory: metadata.priceCategory,
-			promo: metadata.promo,
-		}, {
-			category: 'powerful',
-			priceCategory: 'medium',
-			promo: {
-				id: 'summer-sale',
-				discountPercent: 25,
-				endsAt: '2026-08-01T00:00:00Z',
-				message: 'Save on Claude Sonnet',
+		const infos = await provider.provideLanguageModelChatInfo(undefined, CancellationToken.None);
+		assert.deepStrictEqual(infos.map(info => ({
+			category: info.metadata.category,
+			priceCategory: info.metadata.priceCategory,
+			promo: info.metadata.promo,
+		})), [
+			{
+				category: 'powerful',
+				priceCategory: 'medium',
+				promo: {
+					id: 'summer-sale',
+					discountPercent: 25,
+					endsAt: '2026-08-01T00:00:00Z',
+					message: 'Save on Claude Sonnet',
+				},
 			},
-		});
+			{
+				category: undefined,
+				priceCategory: undefined,
+				promo: { id: 'featured', discountPercent: 0, message: 'Now available' },
+			},
+		]);
 	});
 
 	test('derives the picker group from the model-id prefix, not the harness provider', async () => {

src/vs/workbench/contrib/chat/test/browser/chatPromoNotification.test.ts

@@ -117,6 +117,7 @@ suite('ChatPromoNotificationContribution', () => {
 		const notification = notifService.getNotification();
 		assert.ok(notification, 'Expected a notification to be shown');
 		assert.ok(notification.message.toString().includes('20% off'));
+		assert.ok(notification.description?.toString().includes('2026'), 'Expected the end date to be rendered');
 		assert.deepStrictEqual(notification.actions, [{
 			label: 'Try GPT-5.5',
 			kind: ChatInputNotificationActionKind.SwitchToModel,
@@ -124,17 +125,30 @@ suite('ChatPromoNotificationContribution', () => {
 		}]);
 	});
 
-	test('does not show notification for non-positive promo discounts', () => {
+	test('renders the server message for a 0% promo', () => {
+		const notifService = createMockNotificationService(disposables);
+		const { service: lmService } = createMockLanguageModelsService([{
+			identifier: 'copilot:zero-discount',
+			metadata: { name: 'Zero Discount', id: 'zero-discount', promo: { id: 'promo-zero', discountPercent: 0, endsAt: '2026-07-20T23:59:59Z', message: 'Featured model' } },
+		}], disposables);
+		const storageService = disposables.add(new InMemoryStorageService());
+
+		disposables.add(new ChatPromoNotificationContribution(
+			lmService,
+			notifService.service,
+			storageService,
+		));
+
+		const notification = notifService.getNotification();
+		assert.ok(notification, 'Expected a notification for the 0% promo');
+		assert.strictEqual(notification.message, 'Featured model');
+	});
+
+	test('prefers a discounted promo over a 0% one in the same harness', () => {
 		const notifService = createMockNotificationService(disposables);
 		const { service: lmService } = createMockLanguageModelsService([
-			{
-				identifier: 'copilot:zero-discount',
-				metadata: { name: 'Zero Discount', id: 'zero-discount', promo: { id: 'promo-zero', discountPercent: 0, endsAt: '2026-07-20T23:59:59Z', message: 'Featured model' } },
-			},
-			{
-				identifier: 'copilot:negative-discount',
-				metadata: { name: 'Negative Discount', id: 'negative-discount', promo: { id: 'promo-negative', discountPercent: -10, endsAt: '2026-07-20T23:59:59Z', message: 'Featured model' } },
-			},
+			{ identifier: 'copilot:featured', metadata: { name: 'Featured', id: 'featured', promo: { id: 'promo-zero', discountPercent: 0, message: 'Featured model' } } },
+			{ identifier: 'copilot:discounted', metadata: { name: 'Discounted', id: 'discounted', promo: { id: 'promo-discount', discountPercent: 20, message: 'Get 20% off' } } },
 		], disposables);
 		const storageService = disposables.add(new InMemoryStorageService());
 
@@ -144,9 +158,51 @@ suite('ChatPromoNotificationContribution', () => {
 			storageService,
 		));
 
+		const notification = notifService.getNotification();
+		assert.ok(notification);
+		assert.strictEqual(notification.message, 'Get 20% off');
+	});
+
+	test('does not show notification for negative promo discounts', () => {
+		const notifService = createMockNotificationService(disposables);
+		const { service: lmService } = createMockLanguageModelsService([{
+			identifier: 'copilot:negative-discount',
+			metadata: { name: 'Negative Discount', id: 'negative-discount', promo: { id: 'promo-negative', discountPercent: -10, endsAt: '2026-07-20T23:59:59Z', message: 'Featured model' } },
+		}], disposables);
+		const storageService = disposables.add(new InMemoryStorageService());
+
+		disposables.add(new ChatPromoNotificationContribution(
+			lmService,
+			notifService.service,
+			storageService,
+		));
+
 		assert.strictEqual(notifService.getNotification(), undefined);
 	});
 
+	test('omits the end date when the promo has none', () => {
+		const notifService = createMockNotificationService(disposables);
+		const { service: lmService } = createMockLanguageModelsService([
+			{ identifier: 'local:no-end-date', metadata: { name: 'Open Ended', id: 'no-end-date', promo: { id: 'promo-open', discountPercent: 20, message: 'Get 20% off' } } },
+			{ identifier: 'copilot:bad-end-date', metadata: { name: 'Bad Date', id: 'bad-end-date', targetChatSessionType: 'copilotcli', promo: { id: 'promo-bad-date', discountPercent: 20, endsAt: 'not a date', message: 'Get 20% off' } } },
+		], disposables);
+		const storageService = disposables.add(new InMemoryStorageService());
+
+		disposables.add(new ChatPromoNotificationContribution(
+			lmService,
+			notifService.service,
+			storageService,
+		));
+
+		assert.deepStrictEqual(
+			notifService.getAllNotifications().map(n => ({ message: n.message, description: n.description })),
+			[
+				{ message: 'Get 20% off', description: undefined },
+				{ message: 'Get 20% off', description: undefined },
+			],
+		);
+	});
+
 	test('does not show notification for already-dismissed promo', () => {
 		const notifService = createMockNotificationService(disposables);
 		const { service: lmService } = createMockLanguageModelsService([{

src/vs/workbench/contrib/chat/test/browser/widget/input/modelPicker/modelPickerHover.test.ts

@@ -54,4 +54,26 @@ suite('ModelPickerHover', () => {
 			{ discountPercent: -10, category: 'Powerful', badges: ['High cost'], promoText: undefined },
 		]);
 	});
+
+	test('promo hover text omits the end date when the promo has none', () => {
+		const results = ['2026-07-20T23:59:59Z', 'not a date', undefined].map(endsAt => {
+			const model = createModel(`promo-${endsAt}`, `Promo ${endsAt}`);
+			model.metadata = {
+				...model.metadata,
+				promo: { id: `test-promo-${endsAt}`, discountPercent: 20, endsAt, message: 'Limited time offer' },
+			} as ILanguageModelChatMetadata;
+			const hover = getModelHoverContent(model, false, undefined, NullOpenerService);
+			assert.ok(hover);
+			disposables.add(hover.disposable);
+			const promoText = hover.element.querySelector('.chat-model-hover-promo-text')?.textContent?.trim();
+			// The formatted date is locale/timezone dependent, so only assert on the sentence around it.
+			return promoText?.replace(/Ends .+\.$/, 'Ends <date>.');
+		});
+
+		assert.deepStrictEqual(results, [
+			'Limited time offer Ends <date>.',
+			'Limited time offer',
+			'Limited time offer',
+		]);
+	});
 });

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

@@ -105,8 +105,8 @@ declare module 'vscode' {
 			readonly id: string;
 			/** The discount percentage (e.g. 20 for 20% off). */
 			readonly discountPercent: number;
-			/** ISO 8601 date string indicating when the promotion ends. */
-			readonly endsAt: string;
+			/** ISO 8601 date string indicating when the promotion ends. Omit for open-ended promotions. */
+			readonly endsAt?: string;
 			/** A human-readable message about the promotion. */
 			readonly message: string;
 		};

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

@@ -717,7 +717,7 @@ declare module 'vscode' {
 		readonly promo?: {
 			readonly id: string;
 			readonly discountPercent: number;
-			readonly endsAt: string;
+			readonly endsAt?: string;
 			readonly message: string;
 		};
 		readonly maxInputTokens?: number;