When an API edit is blocked by an AbuseFilter, the response received is particularly unhelpful:
<?xml version="1.0"?><api><error code="hookaborted" info="The modification you tried to make was aborted by an extension hook" /></api>
No indication that it was even due to the abuse filter.
The abuse filter should be modified to use the APIEditBeforeSave to return appropriate information for API edits (see how SpamBlacklist does it, for example). This would probably also require adjusting EditPage to give access the edit summary stored in there.
Or I suppose EditPage could be modified to report the responsible extension whenever a hook aborts an edit, but that seems like it might be harder.