diff --git a/internal/commands/cobra.go b/internal/commands/cobra.go
index be79a10..988e7b9 100644
--- a/internal/commands/cobra.go
+++ b/internal/commands/cobra.go
@@ -2,11 +2,11 @@ package commands
 
 import (
 	"os/exec"
+	"strings"
 
 	"github.com/spf13/cobra"
 
 	"codes/internal/ui"
-	"strings"
 )
 
 // InitCmd represents the init command
diff --git a/internal/commands/commands.go b/internal/commands/commands.go
index f2ddc82..1b31cd4 100644
--- a/internal/commands/commands.go
+++ b/internal/commands/commands.go
@@ -984,7 +984,7 @@ func runClaudeInDirectory(dir string) {
 	}
 
 	// Set environment variables
-	config.SetEnvironmentVarsWithConfig(&selectedConfig, cfg)
+	config.SetEnvironmentVarsWithConfig(&selectedConfig)
 
 	ui.ShowInfo("Using configuration: %s", selectedConfig.Name)
 	ui.ShowInfo("Working directory: %s", dir)
@@ -1187,7 +1187,7 @@ func RunConfigSet(key, value string) {
 		cfg.DefaultBehavior = value
 		ui.ShowSuccess("Default behavior set to: %s", value)
 	default:
-		ui.ShowError("Unknown configuration key: %s", nil)
+		ui.ShowError(fmt.Sprintf("Unknown configuration key: %s", key), nil)
 		fmt.Printf("Available keys: defaultBehavior\n")
 		return
 	}
@@ -1213,7 +1213,7 @@ func RunConfigGet(args []string) {
 		case "defaultBehavior":
 			fmt.Printf("%s: %s\n", key, cfg.DefaultBehavior)
 		default:
-			ui.ShowError("Unknown configuration key: %s", nil)
+			ui.ShowError(fmt.Sprintf("Unknown configuration key: %s", key), nil)
 			fmt.Printf("Available keys: defaultBehavior\n")
 			return
 		}
diff --git a/internal/config/config.go b/internal/config/config.go
index 178e487..0df785b 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -1,13 +1,12 @@
 package config
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
-	"log"
 	"net/http"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 )
 
@@ -27,6 +26,43 @@ type APIConfig struct {
 	Status          string            `json:"status,omitempty"`          // "active", "inactive", "unknown"
 }
 
+// UnmarshalJSON implements custom JSON unmarshaling for APIConfig to support
+// backward compatibility with the old flat config format where ANTHROPIC_BASE_URL
+// and ANTHROPIC_AUTH_TOKEN were top-level fields instead of nested under "env".
+func (a *APIConfig) UnmarshalJSON(data []byte) error {
+	// Use an alias to avoid infinite recursion
+	type Alias APIConfig
+	aux := &struct {
+		*Alias
+		// Legacy flat fields from old config format
+		AnthropicBaseURL   string `json:"ANTHROPIC_BASE_URL"`
+		AnthropicAuthToken string `json:"ANTHROPIC_AUTH_TOKEN"`
+	}{
+		Alias: (*Alias)(a),
+	}
+
+	if err := json.Unmarshal(data, aux); err != nil {
+		return err
+	}
+
+	// Migrate legacy flat fields into the env map
+	if a.Env == nil {
+		a.Env = make(map[string]string)
+	}
+	if aux.AnthropicBaseURL != "" {
+		if _, exists := a.Env["ANTHROPIC_BASE_URL"]; !exists {
+			a.Env["ANTHROPIC_BASE_URL"] = aux.AnthropicBaseURL
+		}
+	}
+	if aux.AnthropicAuthToken != "" {
+		if _, exists := a.Env["ANTHROPIC_AUTH_TOKEN"]; !exists {
+			a.Env["ANTHROPIC_AUTH_TOKEN"] = aux.AnthropicAuthToken
+		}
+	}
+
+	return nil
+}
+
 var ConfigPath string
 
 func init() {
@@ -98,18 +134,27 @@ func TestAPIConfig(config APIConfig) bool {
 	}
 
 	// 构建测试请求体
-	testBody := fmt.Sprintf(`{
-		"model": "%s",
-		"max_tokens": 10,
-		"messages": [
-			{
-				"role": "user",
-				"content": "Hello"
-			}
-		]
-	}`, model)
+	type testMessage struct {
+		Role    string `json:"role"`
+		Content string `json:"content"`
+	}
+	type testRequest struct {
+		Model     string        `json:"model"`
+		MaxTokens int           `json:"max_tokens"`
+		Messages  []testMessage `json:"messages"`
+	}
+
+	reqBody := testRequest{
+		Model:     model,
+		MaxTokens: 10,
+		Messages:  []testMessage{{Role: "user", Content: "Hello"}},
+	}
+	bodyBytes, err := json.Marshal(reqBody)
+	if err != nil {
+		return false
+	}
 
-	req, err := http.NewRequest("POST", apiURL, strings.NewReader(testBody))
+	req, err := http.NewRequest("POST", apiURL, bytes.NewReader(bodyBytes))
 	if err != nil {
 		return false
 	}
@@ -310,15 +355,15 @@ func GetEnvironmentVars(apiConfig *APIConfig) map[string]string {
 
 // SetEnvironmentVars 设置环境变量到当前进程
 func SetEnvironmentVars(apiConfig *APIConfig) {
-	SetEnvironmentVarsWithConfig(apiConfig, nil)
+	SetEnvironmentVarsWithConfig(apiConfig)
 }
 
 // SetEnvironmentVarsWithConfig 使用已加载的配置设置环境变量
-func SetEnvironmentVarsWithConfig(apiConfig *APIConfig, cfg *Config) {
+func SetEnvironmentVarsWithConfig(apiConfig *APIConfig) {
 	envVars := GetEnvironmentVars(apiConfig)
 	for key, value := range envVars {
 		if err := os.Setenv(key, value); err != nil {
-			log.Printf("Warning: Failed to set environment variable %s: %v", key, err)
+			fmt.Fprintf(os.Stderr, "Warning: Failed to set environment variable %s: %v\n", key, err)
 		}
 	}
 }