Send an email immediately, with no review card or composer. Only for a prompt that came from a channel or document thread (the context block says so), where there is nothing to review a draft in. The email is always shown before it is sent, even when the user’s request already spelled the whole thing out: in one turn write it into the thread - recipients, subject, body - ask whether to send it, and stop there. Call this tool only in a later turn, once the user has replied approving that specific email, quoting that reply verbatim in userConfirmation. Being asked to send an email is a request to draft one, never approval to send it, so a userConfirmation quoting the request that asked you to write the email - rather than the reply approving the one you wrote - is wrong. Never call it in the agent session view or in chat: use SendEmail there, whose review card or composer is the confirmation. Takes the same fields as SendEmail; write the body in Markdown, which is rendered to HTML on send.
The body of the email, written as Markdown. A host with a composer (chat) replaces this with the base64url-encoded HTML the composer exported before the tool runs; a host without one (an agent session) leaves the Markdown, and this tool renders it the same way.
to
EmailRecipient[]
Yes
The primary recipients (To field).
cc
EmailRecipient[]
No
Carbon copy recipients (optional).
bcc
EmailRecipient[]
No
Blind carbon copy recipients (optional).
replyingToId
string
No
The ID of a message to reply to (optional). When set, the email is sent as a reply within the same thread.
includeSignature
boolean
No
Per-message signature override, set by the composer’s signature preview — not normally by you. Omit to use the inbox’s default policy (always on a new email; on replies/forwards only when the user enabled it). false excludes the signature for this one email.
userConfirmation
string
Yes
The user’s own message approving this specific email, quoted verbatim - for example their “yes, send it” in reply to the email you wrote out for them. It is a reply to your draft, never the earlier request that asked you to write one: if the user has not yet seen this email, there is nothing to quote here and the tool must not be called. Required: do not paraphrase it, and never supply it yourself.
