fix(ai): honor scoped env in compat API key injection

packages/ai/src/compat.ts

@@ -100,7 +100,7 @@ function withEnvApiKey<TOptions extends StreamOptions>(
 	options: TOptions | undefined,
 ): TOptions | undefined {
 	if (hasExplicitApiKey(options?.apiKey)) return options;
-	const apiKey = getEnvApiKey(model.provider);
+	const apiKey = getEnvApiKey(model.provider, options?.env);
 	if (!apiKey) return options;
 	return { ...options, apiKey } as TOptions;
 }

packages/ai/test/compat-env.test.ts

@@ -0,0 +1,74 @@
+import { afterEach, describe, expect, it } from "vitest";
+import { complete, registerApiProvider, resetApiProviders } from "../src/compat.ts";
+import type { AssistantMessage, Context, Model } from "../src/types.ts";
+import { AssistantMessageEventStream } from "../src/utils/event-stream.ts";
+
+const context: Context = { messages: [{ role: "user", content: "hi", timestamp: Date.now() }] };
+
+const model: Model<"openai-responses"> = {
+	id: "test-model",
+	name: "Test Model",
+	api: "openai-responses",
+	provider: "openai",
+	baseUrl: "https://example.test/v1",
+	reasoning: false,
+	input: ["text"],
+	cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
+	contextWindow: 128000,
+	maxTokens: 4096,
+};
+
+function message(): AssistantMessage {
+	return {
+		role: "assistant",
+		content: [{ type: "text", text: "ok" }],
+		api: model.api,
+		provider: model.provider,
+		model: model.id,
+		usage: {
+			input: 0,
+			output: 0,
+			cacheRead: 0,
+			cacheWrite: 0,
+			totalTokens: 0,
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+		},
+		stopReason: "stop",
+		timestamp: Date.now(),
+	};
+}
+
+describe("compat env API key injection", () => {
+	afterEach(() => {
+		resetApiProviders();
+	});
+
+	it("uses request-scoped env when injecting provider API keys", async () => {
+		let capturedApiKey: string | undefined;
+		registerApiProvider({
+			api: "openai-responses",
+			stream: (_model, _context, options) => {
+				capturedApiKey = options?.apiKey;
+				const stream = new AssistantMessageEventStream();
+				const output = message();
+				stream.push({ type: "start", partial: output });
+				stream.push({ type: "done", reason: "stop", message: output });
+				stream.end(output);
+				return stream;
+			},
+			streamSimple: (_model, _context, options) => {
+				capturedApiKey = options?.apiKey;
+				const stream = new AssistantMessageEventStream();
+				const output = message();
+				stream.push({ type: "start", partial: output });
+				stream.push({ type: "done", reason: "stop", message: output });
+				stream.end(output);
+				return stream;
+			},
+		});
+
+		await complete(model, context, { env: { OPENAI_API_KEY: "scoped-key" } });
+
+		expect(capturedApiKey).toBe("scoped-key");
+	});
+});