add type safety

types.d.ts

@@ -12,9 +12,19 @@ interface GCIResult {
   url: string;
 }
 
-interface APIResult {
-  error?: boolean;
-  payload: string;
+interface APIError {
+  error: true;
+  errorMessage: string;
 }
 
-export { GCIAPIResult, APIResult };
+interface APISuccess<T> {
+  error: false;
+  payload: T;
+}
+
+interface APIQueryParams {
+  query: string;
+  lucky?: string;
+}
+
+type APIResult<T> = APIError | APISuccess<T>;