{"lexicon":1,"id":"money.atmosphere.payment.assertPayer","defs":{"main":{"type":"procedure","description":"Service-auth capability NSID used by an app to assert that a signed-in payer DID was present for an ATM checkout. This method is not exposed as a browser API; ATM verifies lxm in a short-lived service-auth JWT embedded in the private checkout envelope.","input":{"encoding":"application/json","schema":{"type":"object","required":["payerDid"],"properties":{"payerDid":{"type":"string","format":"did","description":"The buyer DID asserted by the app-held user session."},"checkoutToken":{"type":"string","maxLength":512,"description":"Optional ATM checkout/session token this assertion was minted for."}}}},"output":{"encoding":"application/json","schema":{"type":"object","required":["accepted"],"properties":{"accepted":{"type":"boolean"}}}},"errors":[{"name":"InvalidPayerAssertion","description":"The payer assertion JWT was malformed or unusable."},{"name":"PayerAssertionVerificationFailed","description":"The payer assertion JWT failed verification."},{"name":"PayerDidMismatch","description":"The assertion issuer does not match the checkout payerDid."}]}}}