call-adcp-agent

Wire-level invariants for any AdCP buyer call — idempotency_key replay semantics, account oneOf variants, async status:'submitted'+task_id polling, error recovery from adcp_error.issues[]. Load before any per-protocol task skill (adcp-media-buy, adcp-creative, adcp-signals, adcp-governance, adcp-si, adcp-brand) when calling an AdCP agent as a buyer.