Add advisor functionality and tests

packages/types/src/model.ts

@@ -98,6 +98,7 @@ export const modelInfoSchema = z.object({
 	outputPrice: z.number().optional(),
 	cacheWritesPrice: z.number().optional(),
 	cacheReadsPrice: z.number().optional(),
+	supportsAdvisorTool: z.boolean().optional(),
 	longContextPricing: z
 		.object({
 			thresholdTokens: z.number(),

packages/types/src/provider-settings.ts

@@ -207,6 +207,9 @@ const anthropicSchema = apiModelIdProviderModelSchema.extend({
 	anthropicBaseUrl: z.string().optional(),
 	anthropicUseAuthToken: z.boolean().optional(),
 	anthropicBeta1MContext: z.boolean().optional(), // Enable 'context-1m-2025-08-07' beta for 1M context window.
+	anthropicAdvisorEnabled: z.boolean().optional(),
+	anthropicAdvisorModel: z.string().optional(),
+	anthropicAdvisorMaxUses: z.number().int().min(1).optional(),
 })
 
 const openRouterSchema = baseProviderSettingsSchema.extend({

packages/types/src/providers/anthropic.ts

@@ -17,6 +17,7 @@ export const anthropicModels = {
 		cacheWritesPrice: 3.75, // $3.75 per million tokens
 		cacheReadsPrice: 0.3, // $0.30 per million tokens
 		supportsReasoningBudget: true,
+		supportsAdvisorTool: true,
 		// Tiered pricing for extended context (requires beta flag 'context-1m-2025-08-07')
 		tiers: [
 			{
@@ -80,6 +81,7 @@ export const anthropicModels = {
 		cacheWritesPrice: 6.25, // $6.25 per million tokens
 		cacheReadsPrice: 0.5, // $0.50 per million tokens
 		supportsReasoningBudget: true,
+		supportsAdvisorTool: true,
 		// Tiered pricing for extended context (requires beta flag)
 		tiers: [
 			{
@@ -196,6 +198,7 @@ export const anthropicModels = {
 		cacheWritesPrice: 1.25,
 		cacheReadsPrice: 0.1,
 		supportsReasoningBudget: true,
+		supportsAdvisorTool: true,
 		description:
 			"Claude Haiku 4.5 delivers near-frontier intelligence at lightning speeds with extended thinking, vision, and multilingual support.",
 	},

src/api/providers/__tests__/anthropic.spec.ts

@@ -209,6 +209,141 @@ describe("AnthropicHandler", () => {
 			const requestOptions = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[1]
 			expect(requestOptions?.headers?.["anthropic-beta"]).toContain("context-1m-2025-08-07")
 		})
+
+		describe("advisor tool feature", () => {
+			const systemPrompt = "You are a helpful assistant."
+			const messages: Anthropic.Messages.MessageParam[] = [
+				{
+					role: "user",
+					content: [{ type: "text" as const, text: "Hello" }],
+				},
+			]
+
+			it("should include advisor tool beta header when advisor tool is enabled", async () => {
+				const advisorHandler = new AnthropicHandler({
+					apiKey: "test-api-key",
+					apiModelId: "claude-sonnet-4-6",
+					anthropicAdvisorEnabled: true,
+				})
+
+				const stream = advisorHandler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const requestOptions = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[1]
+				expect(requestOptions?.headers?.["anthropic-beta"]).toContain("advisor-tool-2026-03-01")
+			})
+
+			it("should inject advisor tool definition when advisor tool is enabled", async () => {
+				const advisorHandler = new AnthropicHandler({
+					apiKey: "test-api-key",
+					apiModelId: "claude-sonnet-4-6",
+					anthropicAdvisorEnabled: true,
+				})
+
+				const stream = advisorHandler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const callArgs = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[0]
+				expect(callArgs?.tools).toBeDefined()
+				expect(callArgs?.tools).toEqual(
+					expect.arrayContaining([
+						expect.objectContaining({
+							type: "advisor_20260301",
+							name: "advisor",
+							model: "claude-opus-4-6",
+						}),
+					]),
+				)
+			})
+
+			it("should include max_uses in advisor tool definition when configured", async () => {
+				const customMaxUses = 5
+				const advisorHandler = new AnthropicHandler({
+					apiKey: "test-api-key",
+					apiModelId: "claude-sonnet-4-6",
+					anthropicAdvisorEnabled: true,
+					anthropicAdvisorMaxUses: customMaxUses,
+				})
+
+				const stream = advisorHandler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const callArgs = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[0]
+				const advisorTool = callArgs?.tools?.find((tool: any) => tool.type === "advisor_20260301")
+				expect(advisorTool).toBeDefined()
+				expect(advisorTool?.max_uses).toBe(customMaxUses)
+			})
+
+			it("should use custom advisor model when configured", async () => {
+				const customModel = "claude-opus-4-5-20251101"
+				const advisorHandler = new AnthropicHandler({
+					apiKey: "test-api-key",
+					apiModelId: "claude-sonnet-4-6",
+					anthropicAdvisorEnabled: true,
+					anthropicAdvisorModel: customModel,
+				})
+
+				const stream = advisorHandler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const callArgs = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[0]
+				const advisorTool = callArgs?.tools?.find((tool: any) => tool.type === "advisor_20260301")
+				expect(advisorTool).toBeDefined()
+				expect(advisorTool?.model).toBe(customModel)
+			})
+
+			it("should not include advisor tool when advisor tool is disabled", async () => {
+				const stream = handler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const callArgs = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[0]
+				const advisorTool = callArgs?.tools?.find((tool: any) => tool.type === "advisor_20260301")
+				expect(advisorTool).toBeUndefined()
+
+				// Also verify beta header is not present
+				const requestOptions = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[1]
+				const betaHeader = requestOptions?.headers?.["anthropic-beta"]
+				if (betaHeader && typeof betaHeader === "string") {
+					expect(betaHeader).not.toContain("advisor-tool-2026-03-01")
+				}
+			})
+
+			it("should use default advisor model and max_uses when not configured", async () => {
+				const advisorHandler = new AnthropicHandler({
+					apiKey: "test-api-key",
+					apiModelId: "claude-sonnet-4-6",
+					anthropicAdvisorEnabled: true,
+					// No anthropicAdvisorModel or anthropicAdvisorMaxUses provided
+				})
+
+				const stream = advisorHandler.createMessage(systemPrompt, messages)
+
+				for await (const _chunk of stream) {
+					// Consume stream
+				}
+
+				const callArgs = mockCreate.mock.calls[mockCreate.mock.calls.length - 1]?.[0]
+				const advisorTool = callArgs?.tools?.find((tool: any) => tool.type === "advisor_20260301")
+				expect(advisorTool).toBeDefined()
+				expect(advisorTool?.model).toBe("claude-opus-4-6") // default
+				expect(advisorTool?.max_uses).toBe(3) // default
+			})
+		})
 	})
 
 	describe("completePrompt", () => {

src/api/providers/anthropic.ts

@@ -75,8 +75,30 @@ export class AnthropicHandler extends BaseProvider implements SingleCompletionHa
 			betas.push("context-1m-2025-08-07")
 		}
 
+		// Add advisor tool beta flag if enabled
+		if (this.options.anthropicAdvisorEnabled) {
+			betas.push("advisor-tool-2026-03-01")
+		}
+
+		let tools = convertOpenAIToolsToAnthropic(metadata?.tools ?? [])
+
+		// Add advisor tool if enabled
+		if (this.options.anthropicAdvisorEnabled) {
+			const advisorModel = this.options.anthropicAdvisorModel ?? "claude-opus-4-6"
+			const maxUses = this.options.anthropicAdvisorMaxUses ?? 3
+			const advisorToolDef: { type: string; name: string; model: string; max_uses?: number } = {
+				type: "advisor_20260301",
+				name: "advisor",
+				model: advisorModel,
+			}
+			if (maxUses >= 1) {
+				advisorToolDef.max_uses = maxUses
+			}
+			tools.push(advisorToolDef as unknown as Anthropic.Tool)
+		}
+
 		const nativeToolParams = {
-			tools: convertOpenAIToolsToAnthropic(metadata?.tools ?? []),
+			tools,
 			tool_choice: convertOpenAIToolChoiceToAnthropic(metadata?.tool_choice, metadata?.parallelToolCalls),
 		}
 

webview-ui/src/components/settings/providers/Anthropic.tsx

@@ -19,6 +19,7 @@ type AnthropicProps = {
 export const Anthropic = ({ apiConfiguration, setApiConfigurationField }: AnthropicProps) => {
 	const { t } = useAppTranslation()
 	const selectedModel = useSelectedModel(apiConfiguration)
+	const modelInfo = selectedModel?.info
 
 	const [anthropicBaseUrlSelected, setAnthropicBaseUrlSelected] = useState(!!apiConfiguration?.anthropicBaseUrl)
 
@@ -103,6 +104,53 @@ export const Anthropic = ({ apiConfiguration, setApiConfigurationField }: Anthro
 					</div>
 				</div>
 			)}
+			{modelInfo?.supportsAdvisorTool && (
+				<div>
+					<Checkbox
+						checked={apiConfiguration?.anthropicAdvisorEnabled ?? false}
+						onChange={(checked: boolean) => {
+							setApiConfigurationField("anthropicAdvisorEnabled", checked)
+						}}>
+						{t("settings:providers.anthropicAdvisorToolLabel")}
+					</Checkbox>
+					{apiConfiguration?.anthropicAdvisorEnabled && (
+						<div className="mt-2 ml-6 space-y-2">
+							<div>
+								<label className="block text-sm font-medium mb-1">
+									{t("settings:providers.anthropicAdvisorModelLabel")}
+								</label>
+								<select
+									value={apiConfiguration?.anthropicAdvisorModel ?? "claude-opus-4-6"}
+									onChange={(event) => {
+										setApiConfigurationField("anthropicAdvisorModel", event.target.value)
+									}}
+									className="w-full px-2 py-1 rounded border border-vscode-input-border bg-vscode-input-background text-vscode-foreground">
+									<option value="claude-opus-4-6">claude-opus-4-6</option>
+								</select>
+							</div>
+							<div>
+								<label className="block text-sm font-medium mb-1">
+									{t("settings:providers.anthropicAdvisorMaxUsesLabel")}
+								</label>
+								<input
+									type="number"
+									min="1"
+									value={apiConfiguration?.anthropicAdvisorMaxUses ?? 3}
+									onChange={(event) => {
+										const value = event.target.value
+										setApiConfigurationField(
+											"anthropicAdvisorMaxUses",
+											value === "" ? undefined : parseInt(value, 10),
+										)
+									}}
+									placeholder={t("settings:providers.anthropicAdvisorMaxUsesPlaceholder")}
+									className="w-full px-2 py-1 rounded border border-vscode-input-border bg-vscode-input-background text-vscode-foreground"
+								/>
+							</div>
+						</div>
+					)}
+				</div>
+			)}
 		</>
 	)
 }

webview-ui/src/i18n/locales/en/settings.json

@@ -437,6 +437,10 @@
 		"anthropicUseAuthToken": "Pass Anthropic API Key as Authorization header instead of X-Api-Key",
 		"anthropic1MContextBetaLabel": "Enable 1M context window (Beta)",
 		"anthropic1MContextBetaDescription": "Extends context window to 1 million tokens for Claude Sonnet 4.x / Claude Opus 4.6",
+		"anthropicAdvisorToolLabel": "Enable Advisor Tool (Beta)",
+		"anthropicAdvisorModelLabel": "Advisor Model",
+		"anthropicAdvisorMaxUsesLabel": "Max Uses",
+		"anthropicAdvisorMaxUsesPlaceholder": "No limit",
 		"awsBedrock1MContextBetaLabel": "Enable 1M context window (Beta)",
 		"awsBedrock1MContextBetaDescription": "Extends context window to 1 million tokens for Claude Sonnet 4.x / Claude Opus 4.6",
 		"vertex1MContextBetaLabel": "Enable 1M context window (Beta)",