Feature request: expose user bio to bots

[mikerockett]

Antispam bots currently have no way to read a user's bio when they join a group. The Bot API does return user info via getChat for users sharing a group with the bot, but the bio field is excluded unless the user has privately interacted with the bot. The bio is visible to all group members, yet bots are specifically locked out of it. Spammers exploit this gap by putting spam content in their bio, knowing bots can't detect it (my antispam bot is getting plenty of reports about these accounts). MTProto exposes this via users.getFullUser, but rate limits make it impractical at scale (and it's not right to need a userbot for this sort of thing anyway).

Request:

1. Add an optional bio field to ChatMemberUpdated and ChatJoinRequest so bots can evaluate bios on join.
2. Include the bio in getChat responses for any user the bot can already retrieve info for, not only users who have privately messaged the bot. This would help in cases where bots join, update their bio, and then spam an innocent looking message, enticing viewers to open their profiles.

[levlam]

The Bot API does return user info via getChat for users sharing a group with the bot, but the bio field is excluded unless the user has privately interacted with the bot.

This is not true. There is nothing special about bio visibility for bots.

MTProto exposes this via users.getFullUser

And Bot API exposes users.getFullUser via getChat.

Add an optional bio field to ChatMemberUpdated and ChatJoinRequest so bots can evaluate bios on join.

The class ChatJoinRequest has the field bio. ChatMemberUpdated is sent whenever member rights are changed. It can't be sent whenever bio is changed.

[mikerockett]

There is nothing special about bio visibility for bots.

Then why can't bots see them in general (when compared to users)?

And Bot API exposes users.getFullUser via getChat.

getChat returns ChatFullInfo, which contains bio, described as "Optional. Bio of the other party in a private chat". Have I missed some other docs?

It can't be sent whenever bio is changed.

I know when they are sent and am fine with that. It's the content that matters.

It just seems near impossible to get the bio of a seen-user on demand.