diff --git a/package-lock.json b/package-lock.json
index 824b8d98..071a4371 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -7337,6 +7337,7 @@
 				"openai": "6.26.0",
 				"partial-json": "^0.1.7",
 				"proxy-agent": "^6.5.0",
+				"proxy-from-env": "^1.1.0",
 				"typebox": "^1.1.24",
 				"undici": "^7.19.1",
 				"zod-to-json-schema": "^3.24.6"
diff --git a/packages/ai/package.json b/packages/ai/package.json
index f8d7b260..1744a2fd 100644
--- a/packages/ai/package.json
+++ b/packages/ai/package.json
@@ -73,11 +73,12 @@
 		"@aws-sdk/client-bedrock-runtime": "^3.1030.0",
 		"@google/genai": "^1.40.0",
 		"@mistralai/mistralai": "^2.2.0",
-		"typebox": "^1.1.24",
 		"chalk": "^5.6.2",
 		"openai": "6.26.0",
 		"partial-json": "^0.1.7",
 		"proxy-agent": "^6.5.0",
+		"proxy-from-env": "^1.1.0",
+		"typebox": "^1.1.24",
 		"undici": "^7.19.1",
 		"zod-to-json-schema": "^3.24.6"
 	},
diff --git a/packages/ai/src/providers/openai-codex-responses.ts b/packages/ai/src/providers/openai-codex-responses.ts
index dc6b6463..64542b2c 100644
--- a/packages/ai/src/providers/openai-codex-responses.ts
+++ b/packages/ai/src/providers/openai-codex-responses.ts
@@ -711,7 +711,35 @@ type WebSocketConstructor = new (
 	protocols?: string | string[] | { headers?: Record<string, string> },
 ) => WebSocketLike;
 
-function getWebSocketConstructor(): WebSocketConstructor | null {
+let _cachedWebsocket: WebSocketConstructor | null = null;
+async function getWebSocketConstructor(): Promise<WebSocketConstructor | null> {
+	if (_cachedWebsocket) return _cachedWebsocket;
+
+	// bun doesn't respect http proxy envs, ref: https://github.com/oven-sh/bun/issues/15489
+	// TODO: remove this when bun supports proxy envs in websocket.
+	if (
+		process?.versions?.bun &&
+		(process.env.HTTP_PROXY || process.env.HTTPS_PROXY || process.env.http_proxy || process.env.https_proxy)
+	) {
+		const m = await dynamicImport("proxy-from-env");
+		const getProxyForUrl = (m as { getProxyForUrl: (url: string | object | URL) => string }).getProxyForUrl;
+
+		_cachedWebsocket = class extends WebSocket {
+			constructor(url: string | URL, options?: string | string[] | Record<string, unknown>) {
+				let _opts: Record<string, unknown> = {};
+				if (Array.isArray(options) || typeof options === "string") {
+					_opts = { protocols: options };
+				} else {
+					_opts = { ...options };
+				}
+
+				const proxy = getProxyForUrl(url.toString().replace(/^wss:/, "https:").replace(/^ws:/, "http:"));
+				super(url, { ..._opts, ...(proxy ? { proxy } : {}) } as any);
+			}
+		};
+		return _cachedWebsocket;
+	}
+
 	const ctor = (globalThis as { WebSocket?: unknown }).WebSocket;
 	if (typeof ctor !== "function") return null;
 	return ctor as unknown as WebSocketConstructor;
@@ -760,7 +788,7 @@ function scheduleSessionWebSocketExpiry(sessionId: string, entry: CachedWebSocke
 }
 
 async function connectWebSocket(url: string, headers: Headers, signal?: AbortSignal): Promise<WebSocketLike> {
-	const WebSocketCtor = getWebSocketConstructor();
+	const WebSocketCtor = await getWebSocketConstructor();
 	if (!WebSocketCtor) {
 		throw new Error("WebSocket transport is not available in this runtime");
 	}