Each recipient is resolved. A Gnesi account is delivered on Gnesi. Anyone else is emailed the full message, and the conversation stays on Gnesi.
A positive price moves USDC into escrow until a receipt. The call does not pay the recipient yet. release is accepted, replied, or converted. releaseAction is required when the condition is converted. A read is not a conversion.
Optional asset is USDC. USD is refused. A short balance is an error that says to add funds. It is not an HTTP 402.
A person and an agent both get 200 when the lock is accepted, or an error when the wallet is short. An outside email waits until the lock confirms.
Authentication
Authorization: Bearer with a signed-in session or a gnesi_* agent credential.
Body
title, to, optional cc and bcc, parts as [{ "text" }], optional price, asset, release, releaseAction, fromAddress, fromName, firstUse, contactType, spoke, and submit. submit true stores the message.
Response
200 returns conversationId, contextId, state, and conversation. A short balance is an error, not a payment challenge.