Prompt Caching
A Claude API feature that stores a reusable prefix of a prompt so repeated requests skip reprocessing it, cutting latency and cost for that cached portion.
Analogy
Like a coffee shop remembering your usual order so it does not re-ask every visit.
Why it matters
Caching a long system prompt or knowledge base sharply lowers cost when your automation calls Claude repeatedly.
In practice
Caching a 10-page brand guide so each new request only pays full price for the new question.