From 9b44acc8c428d98e000a22355b2d0b939729d6b6 Mon Sep 17 00:00:00 2001
From: luvs01 <27862058+luvs01@users.noreply.github.com>
Date: Mon, 10 Aug 2026 09:39:30 +0900
Subject: [PATCH] fix(images): ignore size headers on bodyless responses

---
 src/server/images.ts        | 3 +++
 tests/server-images.test.ts | 5 ++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/server/images.ts b/src/server/images.ts
index edc710933..c3ee1f464 100644
--- a/src/server/images.ts
+++ b/src/server/images.ts
@@ -84,6 +84,9 @@ export async function readImageResponseBytes(
     cancelUnlockedResponseBody(response, signal.reason);
     throw signal.reason;
   }
+  if (response.body === null) {
+    return { bytes: new Uint8Array(0), oversized: false };
+  }
 
   const maxBytes = options.maxBytes ?? IMAGES_RESPONSE_MAX_BYTES;
   const contentLength = response.headers.get("content-length");
diff --git a/tests/server-images.test.ts b/tests/server-images.test.ts
index 86e09624f..d286c192f 100644
--- a/tests/server-images.test.ts
+++ b/tests/server-images.test.ts
@@ -783,7 +783,10 @@ test("relays a bodyless upstream image status without synthesizing a body", asyn
   globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
     const requestUrl = typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url;
     if (new URL(requestUrl).hostname === "chatgpt.com") {
-      return new Response(null, { status: 204 });
+      return new Response(null, {
+        status: 204,
+        headers: { "content-length": String(IMAGES_RESPONSE_MAX_BYTES + 1) },
+      });
     }
     return originalFetch(input, init);
   }) as typeof fetch;