fix(ai): finalize cloudflare gateway provider support

packages/ai/src/providers/anthropic.ts

@@ -32,6 +32,7 @@ import { headersToRecord } from "../utils/headers.js";
 import { parseJsonWithRepair, parseStreamingJson } from "../utils/json-parse.js";
 import { sanitizeSurrogates } from "../utils/sanitize-unicode.js";
 
+import { resolveCloudflareBaseUrl } from "./cloudflare.js";
 import { buildCopilotDynamicHeaders, hasCopilotVisionInput } from "./github-copilot-headers.js";
 import { adjustMaxTokensForThinking, buildBaseOptions } from "./simple-options.js";
 import { transformMessages } from "./transform-messages.js";
@@ -215,8 +216,8 @@ export interface AnthropicOptions extends StreamOptions {
 	client?: Anthropic;
 }
 
-function mergeHeaders(...headerSources: (Record<string, string> | undefined)[]): Record<string, string> {
-	const merged: Record<string, string> = {};
+function mergeHeaders(...headerSources: (Record<string, string | null> | undefined)[]): Record<string, string | null> {
+	const merged: Record<string, string | null> = {};
 	for (const headers of headerSources) {
 		if (headers) {
 			Object.assign(merged, headers);
@@ -772,17 +773,39 @@ function createClient(
 	// Adaptive thinking models (Opus 4.6, Sonnet 4.6) have interleaved thinking built-in.
 	// The beta header is deprecated on Opus 4.6 and redundant on Sonnet 4.6, so skip it.
 	const needsInterleavedBeta = interleavedThinking && !supportsAdaptiveThinking(model.id);
+	const betaFeatures: string[] = [];
+	if (useFineGrainedToolStreamingBeta) {
+		betaFeatures.push(FINE_GRAINED_TOOL_STREAMING_BETA);
+	}
+	if (needsInterleavedBeta) {
+		betaFeatures.push(INTERLEAVED_THINKING_BETA);
+	}
+
+	if (model.provider === "cloudflare-ai-gateway") {
+		const client = new Anthropic({
+			apiKey: null,
+			authToken: null,
+			baseURL: resolveCloudflareBaseUrl(model),
+			dangerouslyAllowBrowser: true,
+			defaultHeaders: mergeHeaders(
+				{
+					accept: "application/json",
+					"anthropic-dangerous-direct-browser-access": "true",
+					"cf-aig-authorization": `Bearer ${apiKey}`,
+					"x-api-key": null,
+					Authorization: null,
+					...(betaFeatures.length > 0 ? { "anthropic-beta": betaFeatures.join(",") } : {}),
+				},
+				model.headers,
+				optionsHeaders,
+			),
+		});
+
+		return { client, isOAuthToken: false };
+	}
 
 	// Copilot: Bearer auth, selective betas.
 	if (model.provider === "github-copilot") {
-		const betaFeatures: string[] = [];
-		if (useFineGrainedToolStreamingBeta) {
-			betaFeatures.push(FINE_GRAINED_TOOL_STREAMING_BETA);
-		}
-		if (needsInterleavedBeta) {
-			betaFeatures.push(INTERLEAVED_THINKING_BETA);
-		}
-
 		const client = new Anthropic({
 			apiKey: null,
 			authToken: apiKey,
@@ -803,14 +826,6 @@ function createClient(
 		return { client, isOAuthToken: false };
 	}
 
-	const betaFeatures: string[] = [];
-	if (useFineGrainedToolStreamingBeta) {
-		betaFeatures.push(FINE_GRAINED_TOOL_STREAMING_BETA);
-	}
-	if (needsInterleavedBeta) {
-		betaFeatures.push(INTERLEAVED_THINKING_BETA);
-	}
-
 	// OAuth: Bearer auth, Claude Code identity headers
 	if (isOAuthToken(apiKey)) {
 		const client = new Anthropic({

packages/ai/src/providers/cloudflare.ts

@@ -12,6 +12,10 @@ export const CLOUDFLARE_AI_GATEWAY_COMPAT_BASE_URL =
 export const CLOUDFLARE_AI_GATEWAY_OPENAI_BASE_URL =
 	"https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/openai";
 
+/** AI Gateway → Anthropic passthrough. */
+export const CLOUDFLARE_AI_GATEWAY_ANTHROPIC_BASE_URL =
+	"https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic";
+
 export function isCloudflareProvider(provider: string): boolean {
 	return provider === "cloudflare-workers-ai" || provider === "cloudflare-ai-gateway";
 }
@@ -20,11 +24,12 @@ export function isCloudflareProvider(provider: string): boolean {
 export function resolveCloudflareBaseUrl(model: Model<Api>): string {
 	const url = model.baseUrl;
 	if (!url.includes("{")) return url;
-	return url.replace(/\{([A-Z_][A-Z0-9_]*)\}/g, (_match, name: string) => {
+	const baseUrl = url.replace(/\{([A-Z_][A-Z0-9_]*)\}/g, (_match, name: string) => {
 		const value = process.env[name];
 		if (!value) {
 			throw new Error(`${name} is required for provider ${model.provider} but is not set.`);
 		}
 		return value;
 	});
+	return baseUrl;
 }

packages/ai/src/providers/openai-completions.ts

@@ -458,11 +458,20 @@ function createClient(
 		Object.assign(headers, optionsHeaders);
 	}
 
+	const defaultHeaders =
+		model.provider === "cloudflare-ai-gateway"
+			? {
+					...headers,
+					Authorization: headers.Authorization ?? null,
+					"cf-aig-authorization": `Bearer ${apiKey}`,
+				}
+			: headers;
+
 	return new OpenAI({
 		apiKey,
 		baseURL: isCloudflareProvider(model.provider) ? resolveCloudflareBaseUrl(model) : model.baseUrl,
 		dangerouslyAllowBrowser: true,
-		defaultHeaders: headers,
+		defaultHeaders,
 	});
 }
 
@@ -1029,6 +1038,7 @@ function detectCompat(model: Model<"openai-completions">): ResolvedOpenAIComplet
 	const isZai = provider === "zai" || baseUrl.includes("api.z.ai");
 	const isMoonshot = provider === "moonshotai" || provider === "moonshotai-cn" || baseUrl.includes("api.moonshot.");
 	const isCloudflareWorkersAI = provider === "cloudflare-workers-ai" || baseUrl.includes("api.cloudflare.com");
+	const isCloudflareAiGateway = provider === "cloudflare-ai-gateway" || baseUrl.includes("gateway.ai.cloudflare.com");
 
 	const isNonStandard =
 		provider === "cerebras" ||
@@ -1041,9 +1051,10 @@ function detectCompat(model: Model<"openai-completions">): ResolvedOpenAIComplet
 		isMoonshot ||
 		provider === "opencode" ||
 		baseUrl.includes("opencode.ai") ||
-		isCloudflareWorkersAI;
+		isCloudflareWorkersAI ||
+		isCloudflareAiGateway;
 
-	const useMaxTokens = baseUrl.includes("chutes.ai") || isMoonshot;
+	const useMaxTokens = baseUrl.includes("chutes.ai") || isMoonshot || isCloudflareAiGateway;
 
 	const isGrok = provider === "xai" || baseUrl.includes("api.x.ai");
 	const isGroq = provider === "groq" || baseUrl.includes("groq.com");
@@ -1070,7 +1081,7 @@ function detectCompat(model: Model<"openai-completions">): ResolvedOpenAIComplet
 	return {
 		supportsStore: !isNonStandard,
 		supportsDeveloperRole: !isNonStandard,
-		supportsReasoningEffort: !isGrok && !isZai && !isMoonshot,
+		supportsReasoningEffort: !isGrok && !isZai && !isMoonshot && !isCloudflareAiGateway,
 		reasoningEffortMap,
 		supportsUsageInStreaming: true,
 		maxTokensField: useMaxTokens ? "max_tokens" : "max_completion_tokens",
@@ -1088,10 +1099,10 @@ function detectCompat(model: Model<"openai-completions">): ResolvedOpenAIComplet
 		openRouterRouting: {},
 		vercelGatewayRouting: {},
 		zaiToolStream: false,
-		supportsStrictMode: !isMoonshot,
+		supportsStrictMode: !isMoonshot && !isCloudflareAiGateway,
 		cacheControlFormat,
 		sendSessionAffinityHeaders: false,
-		supportsLongCacheRetention: true,
+		supportsLongCacheRetention: !(isCloudflareWorkersAI || isCloudflareAiGateway),
 	};
 }
 

packages/ai/src/providers/openai-responses.ts

@@ -197,11 +197,20 @@ function createClient(
 		Object.assign(headers, optionsHeaders);
 	}
 
+	const defaultHeaders =
+		model.provider === "cloudflare-ai-gateway"
+			? {
+					...headers,
+					Authorization: headers.Authorization ?? null,
+					"cf-aig-authorization": `Bearer ${apiKey}`,
+				}
+			: headers;
+
 	return new OpenAI({
 		apiKey,
 		baseURL: isCloudflareProvider(model.provider) ? resolveCloudflareBaseUrl(model) : model.baseUrl,
 		dangerouslyAllowBrowser: true,
-		defaultHeaders: headers,
+		defaultHeaders,
 	});
 }