diff --git a/backend/internal/service/openai_gateway_messages.go b/backend/internal/service/openai_gateway_messages.go
index 4fe89732..ad8cff0b 100644
--- a/backend/internal/service/openai_gateway_messages.go
+++ b/backend/internal/service/openai_gateway_messages.go
@@ -67,7 +67,7 @@ func (s *OpenAIGatewayService) ForwardAsAnthropic(
 		if err := json.Unmarshal(responsesBody, &reqBody); err != nil {
 			return nil, fmt.Errorf("unmarshal for codex transform: %w", err)
 		}
-		applyCodexOAuthTransform(reqBody, false)
+		applyCodexOAuthTransform(reqBody, false, false)
 		// OAuth codex transform forces stream=true upstream, so always use
 		// the streaming response handler regardless of what the client asked.
 		isStream = true