There's currently an API to list all tasks that ran on a bot, and another API to query all tasks filtered by state/tags.

There is no API to filter tasks that ran on a bot per state/tags. That would be useful.

Either update bots.tasks or tasks.list to either allow filtering by bot or filtering by state/tags, as relevant. I don't have a strong opinion either way.

The challenge is that one is filtering for TaskResultSummary, while the other is filtering for TaskRunResult. The difference is subtle but important. In practice this is transparent for the users.