Decide whether a stored response may be reused without revalidating. Applies the RFC 9111 age and freshness arithmetic (Date, Age, Cache-Control, Expires, Last-Modified) and returns action serve|revalidate|miss, the age and freshness lifetime in whole seconds, and the rule IDs with their clause references. now is an argument: the cache never reads a clock.

Judge one request's preconditions and report the status they decide. Evaluates If-Match, If-Unmodified-Since, If-None-Match and If-Modified-Since in the RFC 9110 section 13.2.2 precedence order, stopping at the first applicable one, and returns status 200|304|412, which rule decided it, and the rule IDs with their clause references.

Judge one HTTP response against the Fetch Standard CORS check. Returns decision allow|block, the violated rule IDs with their clause references, the headers that are missing, and what to send instead. No network: url is parsed for scheme/host/port only.

Walk a redirect chain hop by hop and judge each hop with the CORS check. Reports the ordered redirect events (origin_set_to_null, credentials_dropped), the visible response headers, and the effective Access-Control-Max-Age.

Decide whether a stored response can be reused for an incoming request, per RFC 9111 section 4.1. Compares the fields named by the stored Vary value under that field's normalisation policy and returns match hit|miss, the fields that differ, the normalised Vary members, and the rule IDs with their clause references.