Does the caller hold this capability? (grants of its own reach)

The caller's live grant of capability from for (a person being served; default: its owner and chain root). {allowed, mandate_id, mode, constraints} (0.240.0: an approve-first row in mode ask answers {allowed: false, needs_ask: true, mandate_id, mode: "ask"}: each act needs its own approved ask); when not allowed and there is someone to ask, also grant and ask. One shared agent serving several people checks for each person: a grant from one person is never visible for another. THE REFUSAL ENVELOPE (0.226.0): every refusal caused by missing authority (403 acting for someone, no_spending_policy / per_tx_max_exceeded / budget_exceeded / rate_limit_exceeded -> agent.spending, a connected-service denial -> credential.borrow / mcp.call, max_agents_exceeded) keeps its error and code and adds grant: {capability, selector, mode, constraints?} and ask: {method, path, body} -- POST ask.body (fill reason, and estimated_cost for a budget) to ask the grantor. A freeze (spending_freeze) is the owner's call: code only. A caller with no relationship to the grantor gets the generic refusal and no envelope.