Added request/response validation
diff --git a/tools/metadata_test.go b/tools/metadata_test.go
index 88c7e6d..e5d60cd 100644
--- a/tools/metadata_test.go
+++ b/tools/metadata_test.go
@@ -110,8 +110,9 @@
 
 	_, err := tool.Execute(context.Background(), request)
 	assert.Error(t, err)
-	// The unknown action error should come before authentication
-	assert.Contains(t, err.Error(), "unknown action: unknown")
+	// The validation error should come before authentication
+	assert.Contains(t, err.Error(), "invalid metadata request")
+	assert.Contains(t, err.Error(), "invalid action")
 }
 
 func TestMetadataTool_Execute_StatisticsWithoutCorpus(t *testing.T) {