N1QL-FTS Integration: required user permission is not documented.

I am trying to run query containing SEARCH_QUERY() function call using user with the following permissions:

All Buckets:

    Query and Index Services

        Query Select

    Search Service

        Search Admin

Error message is: u'errors': u'errors': [\{u'msg': u'User does not have credentials to run queries using the CURL() function. Add role query_external_access to allow the query to run.', u'code': 13014}] 

Since I know how SEARCH_QUERY() function was implemented (generally it calls appropriate CURL call), I'm not very surprised with this message and can easily fix it.

But real user has no idea, why this function call requires Query CURL Access permission to be granted.

At least, this information should be documented to avoid confusing cases.