Currently, many functions accept a way to configure bson validation by the bson_validate_flags_t: http://mongoc.org/libbson/current/bson_validate_with_error.html

It would be convenient to set this as a client/database/collection option for applications that expect fields to not pass validation.

Additionally, not all functions accept the validation option (e.g. the superseded mongoc_bulk_operation_insert and mongoc_collection_insert functions).