diff --git a/cli/fork.go b/cli/fork.go
index 0711c76a..802b2b8c 100644
--- a/cli/fork.go
+++ b/cli/fork.go
@@ -42,6 +42,9 @@ func buildForkRequest(targetName, targetType string, traffic, port, memory *int)
 func parseForkArg(arg string) (resourceType, name string, err error) {
 	parts := strings.SplitN(arg, "/", 2)
 	if len(parts) == 1 {
+		if parts[0] == "" {
+			return "", "", fmt.Errorf("resource name must not be empty")
+		}
 		return "", parts[0], nil
 	}
 	name = parts[1]
diff --git a/cli/fork_test.go b/cli/fork_test.go
index c18cb0e0..cbd652e1 100644
--- a/cli/fork_test.go
+++ b/cli/fork_test.go
@@ -19,6 +19,7 @@ func TestParseForkArg(t *testing.T) {
 		{name: "untyped", arg: "source", resourceName: "source"},
 		{name: "sandbox", arg: "sbx/source", resourceType: "sandbox", resourceName: "source"},
 		{name: "application", arg: "application/target", resourceType: "application", resourceName: "target"},
+		{name: "empty name", arg: "", wantErr: "resource name must not be empty"},
 		{name: "missing name", arg: "sbx/", wantErr: "missing name"},
 		{name: "unknown type", arg: "agent/source", wantErr: "unknown resource type"},
 		{name: "nested path", arg: "sbx/foo/bar", wantErr: "must not contain '/'"},