Data validation in ESRI's geodatabases is handled by coded value and range domains. However, the geodatabase doesn't strictly enforce that data input into a feature class or table is valid.
At AmigoCloud, we strictly enforce that all data entered falls within specified coded values and ranges. In order to ensure that your data will be able to sync with AmigoCloud, we do a check on the feature class or table to make sure that all data is valid. If any data is found to be invalid, we report the number of features that are invalid and do not proceed with the sync.
In order to make your data valid, please run the validate tools in ArcMap.
If you are more interested in data validation using Esri tools, look at the ArcGIS Data Reviewer tool.