From 2bd759142023a3cb6e4dd2fd838816d83bb51f95 Mon Sep 17 00:00:00 2001
From: Christopher Pruijsen <christopher.pruijsen@gmail.com>
Date: Thu, 10 Sep 2026 19:13:36 +0100
Subject: [PATCH] fix(js/plugins/compat-oai): omit visualDetailLevel from
 OpenAI request bodies

visualDetailLevel is applied to image_url.detail, but was then spread into the Chat Completions body via restOfConfig and rejected as an unknown parameter.
---
 js/plugins/compat-oai/src/model.ts            |  1 +
 .../compat-oai/tests/compat_oai_test.ts       | 41 +++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/js/plugins/compat-oai/src/model.ts b/js/plugins/compat-oai/src/model.ts
index c5c7df7a96..1c5070e140 100644
--- a/js/plugins/compat-oai/src/model.ts
+++ b/js/plugins/compat-oai/src/model.ts
@@ -578,6 +578,7 @@ export function toOpenAIRequestBody(
     version: modelVersion,
     tools: toolsFromConfig,
     apiKey,
+    visualDetailLevel,
     ...restOfConfig
   } = request.config ?? {};
 
diff --git a/js/plugins/compat-oai/tests/compat_oai_test.ts b/js/plugins/compat-oai/tests/compat_oai_test.ts
index 47ba29c5de..a9209c769f 100644
--- a/js/plugins/compat-oai/tests/compat_oai_test.ts
+++ b/js/plugins/compat-oai/tests/compat_oai_test.ts
@@ -1500,6 +1500,47 @@ describe('toOpenAiRequestBody', () => {
       },
     });
   });
+
+  it('applies visualDetailLevel to image URLs without leaking it into the request body', () => {
+    const request = {
+      messages: [
+        {
+          role: 'user',
+          content: [
+            { text: 'describe this image' },
+            {
+              media: {
+                contentType: 'image/jpeg',
+                url: 'https://example.com/image.jpg',
+              },
+            },
+          ],
+        },
+      ],
+      config: {
+        visualDetailLevel: 'high',
+      },
+    } as GenerateRequest;
+
+    const actualOutput = toOpenAIRequestBody('gpt-4o', request);
+
+    expect(actualOutput).not.toHaveProperty('visualDetailLevel');
+    expect(actualOutput.messages).toStrictEqual([
+      {
+        role: 'user',
+        content: [
+          { type: 'text', text: 'describe this image' },
+          {
+            type: 'image_url',
+            image_url: {
+              url: 'https://example.com/image.jpg',
+              detail: 'high',
+            },
+          },
+        ],
+      },
+    ]);
+  });
 });
 
 describe('openAIModelRunner', () => {