chatbots for to-do list management?

Since there's a bewildering array of sort-of matches from a quick look on Google, I thought I'd just put this out there.

I want to have a chat bot as a "to do" stack / list manager, something like:

> todo.push "blog about AIM todo stack bot" todo: 1 item

> todo.push "AIM bot ideas" todo: 2 items

> todo.list blog about AIM todo stack bot AIM bot ideas

> todo.peek blog about AIM todo stack bot

> todo.pop done: blog about AIM todo stack bot

> todo.list AIM bot ideas

> done.list blog about AIM todo stack bot And so on. It's a chatbot rather than a command line utility or a website because I want it to follow me home and I want it to be private and immediate. This must have been done?