From 8ff40f52e01639df1727b93989104448c43cac83 Mon Sep 17 00:00:00 2001
From: 0-don <don.cryptus@gmail.com>
Date: Tue, 17 Feb 2026 00:00:52 +0100
Subject: [PATCH] fix: remove unsupported parameters from Codex model requests

---
 .../service/openai_codex_transform.go         | 20 ++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/backend/internal/service/openai_codex_transform.go b/backend/internal/service/openai_codex_transform.go
index cea81693..a57f0f99 100644
--- a/backend/internal/service/openai_codex_transform.go
+++ b/backend/internal/service/openai_codex_transform.go
@@ -112,13 +112,19 @@ func applyCodexOAuthTransform(reqBody map[string]any, isCodexCLI bool) codexTran
 		result.Modified = true
 	}
 
-	if _, ok := reqBody["max_output_tokens"]; ok {
-		delete(reqBody, "max_output_tokens")
-		result.Modified = true
-	}
-	if _, ok := reqBody["max_completion_tokens"]; ok {
-		delete(reqBody, "max_completion_tokens")
-		result.Modified = true
+	// Strip parameters unsupported by codex models via the Responses API.
+	for _, key := range []string{
+		"max_output_tokens",
+		"max_completion_tokens",
+		"temperature",
+		"top_p",
+		"frequency_penalty",
+		"presence_penalty",
+	} {
+		if _, ok := reqBody[key]; ok {
+			delete(reqBody, key)
+			result.Modified = true
+		}
 	}
 
 	if normalizeCodexTools(reqBody) {