Operator
Wikimedia Foundation
Wikimedia Foundation runs 2 bots across 2 agent types. Each one is a separate user-agent so you can allow or block them independently.
Bot
IABotWeb Archiver · Archival
Web Archiver
Archival
IABot is operated by Wikimedia Foundation. Preserves web content for archival or historical reference, snapshotting pages so they remain available even after the original is taken down.
WMF CitoidGeneric Crawler · General
Generic Crawler
General
WMF Citoid is operated by Wikimedia Foundation. Generic programmatic data extraction with intent that varies case-by-case. Worth checking the operator before blocking, some are legitimate research, some are abusive.