I’m trying to use the CircleCI API to retrieve details about the latest build for a particular Git tag. It seems like the /project/..../tree/.... API only likes branch names, not tag names 
https://circleci.com/api/v1.1/project/github/yarnpkg/yarn/tree/v0.27.5 returns nothing, even though there is a build for v0.27.5: https://circleci.com/gh/yarnpkg/yarn/4294. Using the branch name (eg. https://circleci.com/api/v1.1/project/github/yarnpkg/yarn/tree/0.27-stable) works fine, but I’m specifically looking for an API to retrieve the latest build for a given tag, not branch.
For comparison, AppVeyor allows both branch names and tag names to be retrieved via their API.