What must hold while work is done: the one policy every provider's instruction file is generated from, the rules and the doctrine that says which of them a machine decides and enforces, and the commit policy every message is judged against. A rule is blocking or advisory, and the difference is a fact the tool reports rather than a word in a document.
Not in this domain: what proves a statement about the product, which is evidence; and the contract a task is finished against, which is completion.