The prompt-caching pricing reference in docs/reference/token-use.md linked to
docs.anthropic.com/docs/build-with-claude/prompt-caching. After Anthropic's
docs migration to platform.claude.com, that URL 301-redirects in an infinite
loop (browsers surface ERR_TOO_MANY_REDIRECTS).
Point it at the current canonical page, which returns HTTP 200 and still
documents the cache read/write pricing and 1h/5m TTL multipliers that the
surrounding paragraph references.