The checker has three posts. Should it produce a growth score?

A small sample can still be useful as a baseline. It cannot support every comparison a polished scorecard suggests. Show the observed posts, collection date and missing fields first; avoid percentile claims without a defined reference population.

The next useful action may be to run a small, consistent content series and collect comparable snapshots. A tool that says what to measure next can be more helpful than a tool that converts three observations into an unexplained score out of 100.