In T204267 the extension flooded the query service with requests and ended up getting all mediawiki requests banned.
In the future other less floody SPARQL requests may come from mediawiki and thus have the same UA & get banned (unless the banning is done by IP only?)
In order to avoid these blankety bans each sub product / service within mediawiki making the requests should add its own product to the UA in addition to the default mediawiki one.
We should also include the name of the wiki that the request is coming from. This is planning for a future where QualityConstraints may also be run on another wikibase instance within the WMF cluster (for example commons).
Current example UA:
MediaWiki/1.32.0-wmf.20
Proposed UA:
MediaWiki/1.32.0-wmf.20 WikibaseQualityConstraints
User-Agent RFC: https://tools.ietf.org/html/rfc7231#section-5.5.3
Pointers
The option probably needs to be added to https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/WikibaseQualityConstraints/+/refs/heads/master/src/ConstraintCheck/Helper/SparqlHelper.php#583 however other usage should be checked..
