/setChatMemberTag <tag> calls setChatMemberTag for that user. The tag is the command's remaining text after removing at most one leading space; it is not otherwise trimmed.
/removeChatMemberTag clears that user's tag by sending null.
/setCanManageTags true invokes promoteChatAdministrator with canManageTags = true. Any remaining text other than exact, lowercase true sets that permission to false.

The bot sends no success reply for these operations and does not register commands in Telegram's command menu.

Message trigger and storage

For every delivered group content message that can be interpreted as potentially coming from a user, the bot sends two replies:

Tag after casting: <tag> using the typed senderTag property;
Tag by getting via risk API: <tag> using the raw sender_tag field.

The displayed value may be null. Command messages also reach this content handler. Tags and tag-management rights are stored by Telegram as chat-member state; this example has no local map, database, or persistence layer. It prints its own bot information at startup and logs every received update.

Setup, permissions, and privacy

Create a bot, obtain its token, and keep it private.
Add it to a test group and allow it to send messages.
Grant the Telegram administrator rights needed to set member tags and promote members/change their canManageTags permission.

To inspect ordinary group messages, configure bot privacy so Telegram delivers them; an administrator bot normally has broader visibility, but verify delivery in the target group. The bot publicly echoes sender tags and logs full updates, so protect the group and process output. The code configures no webhook.

Run

From the repository root:

./gradlew :TagsBot:run --args="BOT_TOKEN"

The first argument is the required token. Optional exact flags may follow it in any order: debug enables formatted logging, and testServer selects Telegram's test environment. Other arguments are ignored.