Why get label names and values from the `/api/v1/series` API, not the `/api/v1/labels` and `/api/v1/label/…/values` API ?

[chenlujjj]

Hi team, is it better to use the /api/v1/labels and /api/v1/label/…/values APIs instead of /api/v1/series API to fetch label names and values when doing auto-completion in code mode and drop-down list in builder mode, because the latter requests much more data from the database, and sometimes get into timeout or hit maxSeries limit?