Cache hit
An answer served from stored data instead of fetched fresh.
What it means
A cache keeps recent answers so repeat requests are fast and do not hit the source again. A hit is a request the cache could answer; a miss is one that needed a fresh fetch.
How Onekey handles it
metadata.cached and the X-Cache: HIT or MISS header say which you got. A cache hit is free; a cached response over 100 KB costs 0.2 credit, never more than the endpoint price. Most endpoints share one cache across customers, and simultaneous identical requests are merged into a single fetch.