diff --git a/pkg/providers/factory_provider.go b/pkg/providers/factory_provider.go
index fb5191bf8..cfd516ee4 100644
--- a/pkg/providers/factory_provider.go
+++ b/pkg/providers/factory_provider.go
@@ -266,22 +266,11 @@ func CreateProviderFromConfig(cfg *config.ModelConfig) (LLMProvider, string, err
 			}
 			return provider, modelID, nil
 		}
-		// Use API key with HTTP API
-		apiBase := cfg.APIBase
-		if apiBase == "" {
-			apiBase = "https://api.anthropic.com/v1"
-		}
+		// Use API key with native Anthropic SDK (not OpenAI-compatible HTTPProvider)
 		if cfg.APIKey() == "" {
 			return nil, "", fmt.Errorf("api_key is required for anthropic protocol (model: %s)", cfg.Model)
 		}
-		return NewHTTPProviderWithMaxTokensFieldAndRequestTimeout(
-			cfg.APIKey(),
-			apiBase,
-			cfg.Proxy,
-			cfg.MaxTokensField,
-			cfg.RequestTimeout,
-			cfg.ExtraBody,
-		), modelID, nil
+		return NewClaudeProviderWithBaseURL(cfg.APIKey(), cfg.APIBase), modelID, nil
 
 	case "anthropic-messages":
 		// Anthropic Messages API with native format (HTTP-based, no SDK)