diff --git a/core/eerrors/errors.go b/core/eerrors/errors.go
index a022bf31..24edc398 100644
--- a/core/eerrors/errors.go
+++ b/core/eerrors/errors.go
@@ -19,6 +19,7 @@ type Error interface {
 	WithMd(map[string]string) Error
 	WithMessage(string) Error
 	WithMsg(string) Error
+	AppendMd(map[string]string) Error
 }
 
 const (
@@ -99,6 +100,15 @@ func (x *EgoError) WithMsg(msg string) Error {
 	return err
 }
 
+// AppendMd appends metadata to current EgoError
+func (x *EgoError) AppendMd(md map[string]string) Error {
+	err := proto.Clone(x).(*EgoError)
+	for k, v := range md {
+		err.Metadata[k] = v
+	}
+	return err
+}
+
 // New returns an error object for the code, message.
 func New(code int, reason, message string) *EgoError {
 	return &EgoError{