Send a Gmail draft
Input
draftId requiredThe draft's current id, as returned by the drafts listing: a new message or a reply saved inside a conversation. Gmail replaces a draft's id every time it is saved, so use a freshly listed one.
account optionalGoogle account email whose draft this is. Without it Gmail opens the first signed-in account (u/0), which may not be the one holding the draft when several accounts share the browser.
Output
sent requiredTrue when the message was actually sent. Always true on success: the script fails loudly instead of returning false.
subject requiredSubject of the message that was sent. Empty when the draft had no subject. For a reply, the subject it carries from its conversation.
threadId requiredConversation id, unchanged by sending, so the sent message can be located afterwards.
account_used requiredThe Gmail account the message was sent from, read from the session rather than assumed.
verified_on_page requiredTrue when the send was confirmed by server-derived evidence: Gmail accepting it, or the message appearing in a settled Sent list (for a reply, together with the draft leaving Drafts).
recipientsDisplay requiredThe recipients as the compose window lists them: display names, which is what Gmail renders there. The addresses are in recipients.
sender optionalThe address the message was sent from: the Gmail account whose mailbox held and sent the draft (same as account_used).
isReply optionalTrue when the draft was a reply saved inside a conversation, false for a new message.
attempts optionalHow many Send clicks it took before Gmail accepted. More than 1 means a click silently failed to reach the server and was retried.
leftDrafts optionalWhether the draft had disappeared from Drafts by the time this was checked. For a new message it is informational, since it depends on the list repainting. For a reply it is this very draft id, and it backs the Sent check.
recipients optionalThe To addresses as the compose window holds them, so the delivery is auditable.
foundInSent optionalWhether the message was found in Sent afterwards, read only once the previous view's draft rows had cleared. For a new message, its conversation; for a reply, its conversation ending on a new message, since the conversation may have been in Sent before.
previousDraftId optionalThe draft id that was sent and therefore no longer exists as a draft.
accepted_by_server optionalTrue when Gmail confirmed it accepted the send: the Undo link's target rewritten to a server-assigned conversation, or Gmail's answer listing the message under Sent.
FAQ
Search Gmail
Search the signed-in Gmail with the native query syntax (from:, to:, subject:, has:attachment, after:/before:, labels…) and return matching threads: threadId (feed it to get_thread / reply_to_email), sender, senderEmail, subject, snippet, date, unread, starred, hasAttachment. Results are threads rather than individual messages, which is Gmail's own search granularity, and only the first page of results is returned (up to 50).
Send Gmail email
Send an email from the signed-in Gmail account, with a plain-text body and an optional single file attachment. Always starts a new conversation. To answer inside an existing thread, use mail.google.com/reply_to_email.
Get Gmail thread
Read a Gmail thread by its hex threadId (as returned by search_emails): subject plus every rendered message's from, fromEmail, to, date, plain-text body and attachment names. In long threads Gmail collapses older messages, so only rendered (expanded) messages are returned.