Prompt caching reduces effective cost for repeated context
description
When a prompt prefix is cached (see subagentcontext.com's prompt-caching concept), reusing that cached prefix across requests is billed more cheaply than reprocessing the same tokens fresh each time.
how it works
This makes prompt caching a direct lever on cost for workflows that repeatedly send the same large system prompt, tool schema, or reference document alongside a smaller varying portion of the request.
source note
Cross-references subagentcontext.com's prompt-caching concept page; general mechanism, grounded in the same prompt-caching doc mirrored in this repo (docs/docs/platform.claude.com/docs/en/build-with-claude/prompt-caching.md), no specific discount percentage asserted since not independently re-verified this session.
provenance
created 2026-07-02 08:30:36 · JSON