Merge pull request #2005 from gaoren002/pr/openai-strip-passthrough-fields

fix(openai): strip unsupported passthrough fields

backend/internal/service/openai_codex_transform.go

@@ -53,6 +53,23 @@ const (
 	codexSparkImageUnsupportedText   = codexSparkImageUnsupportedMarker + "\nThe current model is gpt-5.3-codex-spark, which does not support image generation, image editing, image input, the `image_generation` tool, or Codex `image_gen`/`$imagegen` workflows. If the user asks for image generation or image editing, clearly explain this model limitation and ask them to switch to a non-Spark Codex model such as gpt-5.3-codex or gpt-5.4. Do not claim that the local environment merely lacks image_gen tooling, and do not suggest CLI fallback as the primary fix while the model remains Spark.\n</sub2api-codex-spark-image-unsupported>"
 )
 
+var openAIChatGPTInternalUnsupportedFields = []string{
+	"user",
+	"metadata",
+	"prompt_cache_retention",
+	"safety_identifier",
+	"stream_options",
+}
+
+var openAICodexOAuthUnsupportedFields = append([]string{
+	"max_output_tokens",
+	"max_completion_tokens",
+	"temperature",
+	"top_p",
+	"frequency_penalty",
+	"presence_penalty",
+}, openAIChatGPTInternalUnsupportedFields...)
+
 func applyCodexOAuthTransform(reqBody map[string]any, isCodexCLI bool, isCompact bool) codexTransformResult {
 	result := codexTransformResult{}
 	// 工具续链需求会影响存储策略与 input 过滤逻辑。
@@ -93,23 +110,8 @@ func applyCodexOAuthTransform(reqBody map[string]any, isCodexCLI bool, isCompact
 		}
 	}
 
-	// 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",
-		// prompt_cache_retention is a newer Responses API parameter (cache TTL).
-		// The ChatGPT internal Codex endpoint rejects it with
-		// "Unsupported parameter: prompt_cache_retention". Defense-in-depth
-		// for any OAuth path that reaches this transform — the Cursor
-		// Responses-shape short-circuit in ForwardAsChatCompletions strips
-		// it earlier too, but we keep this line so other OAuth callers are
-		// equally protected.
-		"prompt_cache_retention",
-	} {
+	// Strip parameters unsupported by ChatGPT internal Codex endpoint.
+	for _, key := range openAICodexOAuthUnsupportedFields {
 		if _, ok := reqBody[key]; ok {
 			delete(reqBody, key)
 			result.Modified = true