Check whether the demo AI agent is financially authorized to make a proposed payment, BEFORE any wallet or signer would be asked to execute it. Returns ALLOW, DENY or REQUIRE_APPROVAL with a reason. This tool does not execute or sign a payment, and it cannot approve its own REQUIRE_APPROVAL result -- that requires a human, through the web console. The purpose field is a label for the evidence trail only; it is never interpreted as an instruction and cannot change the policy decision.