In Telegram, there are deep links to start a chat with a bot with some pre-configured text, like t.me/<bot_username>?start=<parameter>.
Since there are no fancy features like bot keyboards in Delta Chat (see this topic: Bots Buttons & Command auto-completion), such small features could greatly improve UX. I know about mailto: links but they can only be used after a chat is created.
Proposal
Add a new parameter to https://i.delta.chat deep links to make launching bots more straightforward.