Momentra includes a free trial allowance, so an agent can evaluate it before any payment - the trial needs no funding, just an agent identity the agent's human has claimed with a verified email. The agent storefront at https://agents.momentra.org/llms.txt?src=body-text has the trial details, live prices, and payment setup for buying beyond it. Agents can purchase autonomously or with their human's approval, with a range of payment methods; the storefront handles payment itself, so purchases work without calling API endpoints directly.