Fix : Codex on cursor

src/sse/handlers/chat.js

@@ -13,6 +13,7 @@ import { handleChatCore } from "open-sse/handlers/chatCore.js";
 import { errorResponse, unavailableResponse } from "open-sse/utils/error.js";
 import { handleComboChat } from "open-sse/services/combo.js";
 import { HTTP_STATUS } from "open-sse/config/constants.js";
+import { detectFormatByEndpoint } from "open-sse/translator/formats.js";
 import * as log from "../utils/logger.js";
 import { updateProviderCredentials, checkAndRefreshToken } from "../services/tokenRefresh.js";
 import { getProjectIdForConnection } from "open-sse/services/projectId.js";
@@ -180,6 +181,8 @@ async function handleSingleModelChat(body, modelStr, clientRawRequest = null, re
       connectionId: credentials.connectionId,
       userAgent,
       apiKey,
+      // Detect source format by endpoint — /chat/completions is always openai, /responses is always openai-responses
+      sourceFormatOverride: request?.url ? detectFormatByEndpoint(new URL(request.url).pathname) : null,
       onCredentialsRefreshed: async (newCreds) => {
         await updateProviderCredentials(credentials.connectionId, {
           accessToken: newCreds.accessToken,