Pagure is not able to change issues' tags via API, and probably never will: https://pagure.io/pagure/issue/4761
Use issue custom field instead. Even though the custom field can not be created via API, it is a smaller hassle to create it by hand once per each repo, instead of being unable to change the SP value from the web UI in the future.
Metadata Update from @jskladan: - Custom field stage adjusted to None - Custom field story points adjusted to 1 - Issue assigned to jskladan
Metadata Update from @jskladan: - Custom field story points reset (from 1)
Metadata Update from @jskladan: - Custom field story points adjusted to 1
Metadata Update from @jskladan: - Custom field story points reset (from 1) - Issue status updated to: Closed (was: Open)
Metadata Update from @jskladan: - Custom field story points adjusted to 2
Metadata Update from @jskladan: - Custom field story points reset (from 2) - Issue status updated to: Open (was: Closed)
Metadata Update from @jskladan: - Issue status updated to: Closed (was: Open)
Metadata Update from @jskladan: - Custom field story points adjusted to 3
Metadata Update from @jskladan: - Custom field story points reset (from 3) - Issue status updated to: Open (was: Closed)
Metadata Update from @jskladan: - Custom field story points adjusted to 2 - Issue marked as depending on: #6
Metadata Update from @jskladan: - Issue unmarked as depending on: #6 - Issue marked as blocking: #6
Metadata Update from @jskladan: - Custom field story points reset (from 2) - Issue status updated to: Closed (was: Open)
Metadata Update from @jskladan: - Custom field foobar adjusted to 3 - Custom field story_points adjusted to 4
Metadata Update from @jskladan: - Issue status updated to: Open (was: Closed)
Metadata Update from @jskladan: - Custom field foo bar adjusted to 2
Metadata Update from @jskladan: - Custom field story_points adjusted to 2 (was: 4)
Metadata Update from @jskladan: - Custom field story points adjusted to 12
Metadata Update from @jskladan: - Custom field story points reset (from 12) - Issue status updated to: Closed (was: Open)
Metadata Update from @jskladan: - Custom field story points adjusted to 13
Metadata Update from @jskladan: - Custom field story points reset (from 13) - Issue status updated to: Closed (was: Open)
Metadata Update from @jskladan: - Issue unmarked as blocking: #6
Metadata Update from @jskladan: - Custom field story_points adjusted to 15
Metadata Update from @jskladan: - Custom field story_points adjusted to 1 (was: 15)