From 77deaff4808cfa00b7a81c8545da2854ae57c0d8 Mon Sep 17 00:00:00 2001
From: Ege Arhan <egearhany@gmail.com>
Date: Wed, 4 Nov 2026 17:30:58 +0300
Subject: [PATCH] fix(web-search): strip responses-lite header from OpenAI
 sidecar requests

---
 src/web-search/executor.ts          |  8 ++++---
 tests/web-search/web-search.test.ts | 37 +++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/src/web-search/executor.ts b/src/web-search/executor.ts
index 6a1e11acf81..6e2a74e5ab2 100644
--- a/src/web-search/executor.ts
+++ b/src/web-search/executor.ts
@@ -1,5 +1,5 @@
 import type { OcxProviderConfig } from "../types";
-import { mergeCodexSelectedHeaders } from "../codex/forward-transport-headers";
+import { CODEX_RESPONSES_LITE_HEADER, mergeCodexSelectedHeaders } from "../codex/forward-transport-headers";
 import { signalWithTimeout, cancelBodyOnAbort } from "../lib/abort";
 import { redactSecretString } from "../lib/redact";
 import { sidecarEnter } from "../lib/sidecar-tracker";
@@ -84,9 +84,11 @@ export async function runWebSearch(
   if (settings.reserveCompatibility && settings.model === NATIVE_RESERVE_MODEL) {
     return { text: "", sources: [], error: "Luna Reserve compatibility is only available as a conversation model, not a search helper. Choose another search helper model." };
   }
-  const headers = Object.fromEntries(mergeCodexSelectedHeaders(
+  const mergedHeaders = mergeCodexSelectedHeaders(
     { "Content-Type": "application/json", ...forwardProvider.headers }, selectedForwardHeaders,
-  ));
+  );
+  mergedHeaders.delete(CODEX_RESPONSES_LITE_HEADER);
+  const headers = Object.fromEntries(mergedHeaders);
   const body = {
     model: settings.model,
     instructions: settings.describeImages ? BASE_INSTRUCTION + IMAGE_INSTRUCTION : BASE_INSTRUCTION,
diff --git a/tests/web-search/web-search.test.ts b/tests/web-search/web-search.test.ts
index 4e8a86920b9..a50b52ed2b8 100644
--- a/tests/web-search/web-search.test.ts
+++ b/tests/web-search/web-search.test.ts
@@ -725,6 +725,43 @@ test("OpenAI web-search execution uses the pinned canonical URL and selected cre
   expect(observedProtocol).toBe("http1.1");
 });
 
+test("issue #8160 - OpenAI search helper strips responses-lite marker from merged headers", async () => {
+  const originalFetch = globalThis.fetch;
+  let capturedHeaders: Headers | undefined;
+  globalThis.fetch = (async (_url: any, init: any) => {
+    capturedHeaders = new Headers(init?.headers);
+    return new Response(
+      'data: ' + JSON.stringify({ type: "response.completed", response: { status: "completed", output: [] } }) + '\n\n',
+      { headers: { "content-type": "text/event-stream" } },
+    );
+  }) as typeof fetch;
+
+  try {
+    await runOpenAiWebSearch(
+      "synthetic query",
+      { type: "web_search" },
+      {
+        adapter: "openai-responses",
+        authMode: "forward",
+        baseUrl: "https://chatgpt.com/backend-api/codex",
+        headers: { "x-openai-internal-codex-responses-lite": "true", "x-custom-test": "forwarded" },
+      } as any,
+      new Headers({
+        "x-openai-internal-codex-responses-lite": "true",
+        "chatgpt-account-id": "test-account",
+      }),
+      { model: "gpt-6.1-sol", reasoning: "low", timeoutMs: 1_000 },
+    );
+
+    expect(capturedHeaders).toBeDefined();
+    expect(capturedHeaders!.has("x-openai-internal-codex-responses-lite")).toBe(false);
+    expect(capturedHeaders!.get("chatgpt-account-id")).toBe("test-account");
+    expect(capturedHeaders!.get("x-custom-test")).toBe("forwarded");
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
 async function collectSse(stream: ReadableStream<Uint8Array>): Promise<{ event?: string; data: Record<string, unknown> }[]> {
   const reader = stream.getReader();
   const decoder = new TextDecoder();