Integrity Check
An automated comparison of each asset's current price against the most recent candle in its own stored history, run periodically to surface unit and mapping errors.
Live prices and price history reach us by separate paths, and that redundancy is what makes the check possible: if the two disagree by an order of magnitude, one is wrong without needing an outside reference. It is how we found a class of currency pairs stored inverted, and ten coins that had inherited another project's history through a shared ticker symbol.