diff --git a/backend/internal/service/openai_codex_transform.go b/backend/internal/service/openai_codex_transform.go
index d1920140b2..b0e4d44fb7 100644
--- a/backend/internal/service/openai_codex_transform.go
+++ b/backend/internal/service/openai_codex_transform.go
@@ -1,6 +1,7 @@
 package service
 
 import (
+	"fmt"
 	"strings"
 )
 
@@ -226,6 +227,29 @@ func normalizeCodexModel(model string) string {
 	return "gpt-5.1"
 }
 
+func SupportsVerbosity(model string) bool {
+	if !strings.HasPrefix(model, "gpt-") {
+		return true
+	}
+
+	var major, minor int
+	n, _ := fmt.Sscanf(model, "gpt-%d.%d", &major, &minor)
+
+	if major > 5 {
+		return true
+	}
+	if major < 5 {
+		return false
+	}
+
+	// gpt-5
+	if n == 1 {
+		return true
+	}
+
+	return minor >= 3
+}
+
 func getNormalizedCodexModel(modelID string) string {
 	if modelID == "" {
 		return ""
diff --git a/backend/internal/service/openai_gateway_service.go b/backend/internal/service/openai_gateway_service.go
index 54068f2b2f..e470745532 100644
--- a/backend/internal/service/openai_gateway_service.go
+++ b/backend/internal/service/openai_gateway_service.go
@@ -1758,6 +1758,14 @@ func (s *OpenAIGatewayService) Forward(ctx context.Context, c *gin.Context, acco
 			bodyModified = true
 			markPatchSet("model", normalizedModel)
 		}
+
+		// 移除 gpt-5.2-codex 以下的版本 verbosity 参数
+		// 确保高版本模型向低版本模型映射不报错
+		if !SupportsVerbosity(normalizedModel) {
+			if text, ok := reqBody["text"].(map[string]any); ok {
+				delete(text, "verbosity")
+			}
+		}
 	}
 
 	// 规范化 reasoning.effort 参数（minimal -> none），与上游允许值对齐。