diff --git a/internal/plugin/metadata_legacy.go b/internal/plugin/metadata_legacy.go
index 8f74d44cb..562a0287e 100644
--- a/internal/plugin/metadata_legacy.go
+++ b/internal/plugin/metadata_legacy.go
@@ -68,11 +68,11 @@ type MetadataLegacy struct {
 }
 
 func (m *MetadataLegacy) Validate() error {
+	if m.Name == "" {
+		return fmt.Errorf("missing plugin name")
+	}
 	if !validPluginName.MatchString(m.Name) {
-		if m.Name == "" {
-			return fmt.Errorf("plugin name is empty or missing: ensure plugin.yaml contains 'name:' field (lowercase)")
-		}
-		return fmt.Errorf("invalid plugin name %q: plugin names can only contain ASCII characters a-z, A-Z, 0-9, _ and -", m.Name)
+		return fmt.Errorf("invalid plugin name %q: must contain only a-z, A-Z, 0-9, _ and -", m.Name)
 	}
 	m.Usage = sanitizeString(m.Usage)
 
diff --git a/internal/plugin/metadata_v1.go b/internal/plugin/metadata_v1.go
index 81dbc2e20..5e83bd352 100644
--- a/internal/plugin/metadata_v1.go
+++ b/internal/plugin/metadata_v1.go
@@ -47,8 +47,11 @@ type MetadataV1 struct {
 }
 
 func (m *MetadataV1) Validate() error {
+	if m.Name == "" {
+		return fmt.Errorf("missing plugin `name`")
+	}
 	if !validPluginName.MatchString(m.Name) {
-		return fmt.Errorf("invalid plugin `name`")
+		return fmt.Errorf("invalid plugin `name` %q: must contain only a-z, A-Z, 0-9, _ and -", m.Name)
 	}
 
 	if m.APIVersion != "v1" {