Bilibili user numeric IDs (mid). Used in 'user_profile' and 'user_videos' modes. Find a user's mid in their profile URL: space.bilibili.com/{mid} — pasting that link works too; a channel name does not. In 'user_profile' mode each creator returns ONE row — followers, following, video count, total likes, level, verification and bio — from one request per creator, no search involved; maxResults caps how many profiles a run returns, and an id Bilibili has no profile for is named in the run status and not charged. Schedule it daily or weekly to track follower growth. How 'user_videos' mode works, so the row count is not a surprise: Bilibili's direct space listing is behind risk control that rejects plain HTTP requests, so the Actor searches the creator's channel name and keeps the videos whose mid matches. It reads that search by date first, where the matches are the creator's newest uploads. When other people's videos crowd it (a famous name is on many fans' clips), the rest come from the relevance-ranked search, which favours the creator's best-known videos and can skip recent uploads — the run status says when that happened. Delivered newest first; for a well-known creator expect about 20 videos, not a complete upload list. For a wider sweep use 'search' mode with the creator's name.