Login account name (distinct from the display name).
Internal numeric user ID.
NOTE: certain API endpoints return this as a string. The core library
normalises it to number before returning it to callers.
OptionalisWhether this user accepts illustration commission requests.
OptionalisWhether this user has blocked access by the authenticated user.
OptionalisWhether the authenticated user follows this user.
Display name shown on the user's profile.
Set of profile image URLs at different sizes.
Minimal user info embedded in works, search results, and preview lists.
Full profile data is returned by GET /v1/user/detail.