Default CLI config path to ~/.config/mcp/mcp.toml

Eliminates the need to pass --config on every command.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cmd/mcp/main.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"path/filepath"
 
 	"github.com/spf13/cobra"
 )
@@ -18,7 +19,11 @@ func main() {
 		Use:   "mcp",
 		Short: "Metacircular Control Plane CLI",
 	}
-	root.PersistentFlags().StringVarP(&cfgPath, "config", "c", "", "config file path")
+	defaultCfg := ""
+	if home, err := os.UserHomeDir(); err == nil {
+		defaultCfg = filepath.Join(home, ".config", "mcp", "mcp.toml")
+	}
+	root.PersistentFlags().StringVarP(&cfgPath, "config", "c", defaultCfg, "config file path")
 
 	root.AddCommand(&cobra.Command{
 		Use:   "version",