diff --git a/internal/config/config.go b/internal/config/config.go
index 5b612ec..bfab72e 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -51,6 +51,8 @@ You may run "ls-config" to show or dump the current config.`
 
 var Validate = config.Validate
 
+var ErrProviderNameConflict = gperr.New("provider name conflict")
+
 func newConfig() *Config {
 	return &Config{
 		value:      config.DefaultConfig(),
@@ -263,56 +265,48 @@ func (cfg *Config) initAutoCert(autocertCfg *autocert.AutocertConfig) (err gperr
 }
 
 func (cfg *Config) errIfExists(p *proxy.Provider) gperr.Error {
-	if _, ok := cfg.providers.Load(p.String()); ok {
-		return gperr.Errorf("provider %s already exists", p.String())
+	if conflict, ok := cfg.providers.Load(p.String()); ok {
+		return ErrProviderNameConflict.
+			Subject(p.String()).
+			Withf("one is %q", conflict.Type()).
+			Withf("the other is %q", p.Type())
 	}
 	return nil
 }
 
-func (cfg *Config) storeProvider(p *proxy.Provider) {
-	cfg.providers.Store(p.String(), p)
-}
-
 func (cfg *Config) loadRouteProviders(providers *config.Providers) gperr.Error {
 	errs := gperr.NewBuilder("route provider errors")
 	results := gperr.NewBuilder("loaded route providers")
 
 	removeAllAgents()
 
+	routeProviders := make([]*proxy.Provider, 0, len(providers.Agents)+len(providers.Docker)+len(providers.Files))
+
 	for _, agent := range providers.Agents {
 		if err := agent.Init(cfg.task.Context()); err != nil {
 			errs.Add(err.Subject(agent.String()))
 			continue
 		}
 		addAgent(agent)
-		p := proxy.NewAgentProvider(agent)
-		if err := cfg.errIfExists(p); err != nil {
-			errs.Add(err.Subject(p.String()))
-			continue
-		}
-		cfg.storeProvider(p)
+		routeProviders = append(routeProviders, proxy.NewAgentProvider(agent))
 	}
 	for _, filename := range providers.Files {
-		p, err := proxy.NewFileProvider(filename)
-		if err == nil {
-			err = cfg.errIfExists(p)
-		}
-		if err != nil {
-			errs.Add(gperr.PrependSubject(filename, err))
-			continue
-		}
-		cfg.storeProvider(p)
+		routeProviders = append(routeProviders, proxy.NewFileProvider(filename))
 	}
 	for name, dockerHost := range providers.Docker {
-		p := proxy.NewDockerProvider(name, dockerHost)
+		routeProviders = append(routeProviders, proxy.NewDockerProvider(name, dockerHost))
+	}
+	if len(routeProviders) == 0 {
+		return nil
+	}
+
+	// check if all providers are unique (should not happen but just in case)
+	for _, p := range routeProviders {
 		if err := cfg.errIfExists(p); err != nil {
-			errs.Add(err.Subject(p.String()))
+			errs.Add(err)
 			continue
 		}
-		cfg.storeProvider(p)
-	}
-	if cfg.providers.Size() == 0 {
-		return nil
+		cfg.providers.Store(p.String(), p)
 	}
 
 	lenLongestName := 0
diff --git a/internal/config/types/config.go b/internal/config/types/config.go
index 3db2ceb..bad04b2 100644
--- a/internal/config/types/config.go
+++ b/internal/config/types/config.go
@@ -2,12 +2,15 @@ package types
 
 import (
 	"context"
+	"os"
+	"path"
 	"regexp"
 	"sync"
 
 	"github.com/go-playground/validator/v10"
 	"github.com/yusing/go-proxy/agent/pkg/agent"
 	"github.com/yusing/go-proxy/internal/autocert"
+	"github.com/yusing/go-proxy/internal/common"
 	"github.com/yusing/go-proxy/internal/gperr"
 	"github.com/yusing/go-proxy/internal/net/gphttp/accesslog"
 	"github.com/yusing/go-proxy/internal/notif"
@@ -24,10 +27,10 @@ type (
 		TimeoutShutdown int                      `json:"timeout_shutdown" validate:"gte=0"`
 	}
 	Providers struct {
-		Files        []string                   `json:"include" yaml:"include,omitempty" validate:"dive,filepath"`
-		Docker       map[string]string          `json:"docker" yaml:"docker,omitempty" validate:"non_empty_docker_keys,dive,unix_addr|url"`
-		Agents       []*agent.AgentConfig       `json:"agents" yaml:"agents,omitempty"`
-		Notification []notif.NotificationConfig `json:"notification" yaml:"notification,omitempty"`
+		Files        []string                   `json:"include" yaml:"include,omitempty" validate:"unique,dive,config_file_exists"`
+		Docker       map[string]string          `json:"docker" yaml:"docker,omitempty" validate:"unique,dive,unix_addr|url"`
+		Agents       []*agent.AgentConfig       `json:"agents" yaml:"agents,omitempty" validate:"unique=Addr"`
+		Notification []notif.NotificationConfig `json:"notification" yaml:"notification,omitempty" validate:"unique=ProviderName"`
 	}
 	Entrypoint struct {
 		Middlewares []map[string]any  `json:"middlewares"`
@@ -97,13 +100,9 @@ func init() {
 		}
 		return true
 	})
-	utils.MustRegisterValidation("non_empty_docker_keys", func(fl validator.FieldLevel) bool {
-		m := fl.Field().Interface().(map[string]string)
-		for k := range m {
-			if k == "" {
-				return false
-			}
-		}
-		return true
+	utils.MustRegisterValidation("config_file_exists", func(fl validator.FieldLevel) bool {
+		filename := fl.Field().Interface().(string)
+		info, err := os.Stat(path.Join(common.ConfigBasePath, filename))
+		return err == nil && !info.IsDir()
 	})
 }
diff --git a/internal/route/provider/event_handler.go b/internal/route/provider/event_handler.go
index 2f2b939..73e2c16 100644
--- a/internal/route/provider/event_handler.go
+++ b/internal/route/provider/event_handler.go
@@ -73,7 +73,7 @@ func (handler *EventHandler) matchAny(events []watcher.Event, route *route.Route
 }
 
 func (handler *EventHandler) match(event watcher.Event, route *route.Route) bool {
-	switch handler.provider.GetType() {
+	switch handler.provider.Type() {
 	case types.ProviderTypeDocker, types.ProviderTypeAgent:
 		return route.Container.ContainerID == event.ActorID ||
 			route.Container.ContainerName == event.ActorName
diff --git a/internal/route/provider/file.go b/internal/route/provider/file.go
index 6c23a60..84bf84f 100644
--- a/internal/route/provider/file.go
+++ b/internal/route/provider/file.go
@@ -20,17 +20,12 @@ type FileProvider struct {
 	l        zerolog.Logger
 }
 
-func FileProviderImpl(filename string) (ProviderImpl, error) {
-	impl := &FileProvider{
+func FileProviderImpl(filename string) ProviderImpl {
+	return &FileProvider{
 		fileName: filename,
 		path:     path.Join(common.ConfigBasePath, filename),
 		l:        logging.With().Str("type", "file").Str("name", filename).Logger(),
 	}
-	_, err := os.Stat(impl.path)
-	if err != nil {
-		return nil, err
-	}
-	return impl, nil
 }
 
 func validate(data []byte) (routes route.Routes, err gperr.Error) {