here’s the current list. Sorry we can’t publish it more proactively, but you can always ask in this thread. It does not change very often these days. This is a regular expression looking for substrings in user agents, case-insensitively.
baiduspider|twitterbot|facebookexternalhit|facebot|rogerbot|linkedinbot|embedly|quora link preview|showyoubot|SocialFlow|Net::Curl::Simple|Snipcart|Googlebot|outbrain|pinterestbot|pinterest/0|slackbot|vkShare|W3C_Validator|redditbot|Mediapartners-Google|AdsBot-Google|parsely|DuckDuckBot|whatsapp|Hatena|Screaming Frog SEO Spider|bingbot|Sajaribot|DashLinkPreviews|Discordbot|RankSonicBot|lyticsbot|YandexBot/|YandexWebmaster/|naytev-url-scraper|newspicksbot/|Swiftbot/|mattermost|Applebot/|snapchat|viber|proximic|iframely/|upday|Google Web Preview|AhrefsBot/|AhrefsSiteAudit/|GoogleSites|PetalBot