IMPROVE

src/lib/validCaptchaParams.js

     typeof params.success === 'number' &&
     typeof params.gt === 'string' &&
     typeof params.challenge === 'string',
-    'captcha params must be an object have success(Number) gt(String) challenge(String), but get %s', params
+    'captcha params must be an object have \
+    success(Number) gt(String) challenge(String), but get %s',
+    JSON.stringify(params)
   )
 }