const result = await agent.email({
  to: 'recipient@example.com',          // string | string[]; optional only when replying
  subject: 'Hello from my agent',        // optional only when replying
  body: 'This email was sent autonomously.',
  maxCost: 0.05,
  memo: 'intro outreach',
});
// result.status, result.email?.{ id, provider_message_id, status }, result.domain, result.warning

Options (EmailToolOptions):

Field	Notes
`to`	`string \| string[]`. Required unless `reply_to_email_id` is set.
`subject`	Required unless replying (then defaults to `Re: <original>`).
`body`	Required. Plain text/markdown body.
`reply_to_email_id`	Reply within a thread using an inbound email id from `inboxList()`/`inboxGet()`. Server resolves `In-Reply-To`/`References` and derives `to`/`subject` if omitted.
`from_domain`	Pin a specific sending domain (bypasses warmup rotation — see below).
`from_mailbox`	Local-part, defaults to `agent` (i.e. `agent@from_domain`).
`from_name`	Display name, e.g. `"Jane Doe"` → `Jane Doe <jane@domain>`.
`attachments`	`Array<{ filename?, content?, url?, content_type? }>` — `content` is base64, or pass a `url`.

Plus shared options (maxCost, wait, memo, idempotencyKey, …) from the oneshot skill. email honors idempotencyKey — reuse the same key on retry to avoid double-sends.

Sending domains & warmup (important)

OneShot protects deliverability with a pool of warmed sending domains:

Rotate mode (recommended): omit from_domain/from_mailbox. The server picks a warmed domain from the agent's pool. The chosen address comes back on the response.
Pin mode: set from_domain to force a specific domain — this bypasses warmup protection.

If a pinned domain is still warming or over its daily limit, the send still proceeds but result.warning is set (pinned_domain_warming / pinned_over_limit) — back off accordingly. An un-pinned send with no eligible owned domain is a hard 400 no_sending_domain (there is no shared fallback sender; the agent must own a sending domain — first send provisions one, ~$10 one-time).

Manage the domain pool

const pool = await agent.listDomains();      // { agent_id, domains: [{ domain, pool_status, warmup_score, daily_send_limit, daily_sent_count, ... }] }
await agent.pauseDomain('mydomain.com');     // remove from rotation
await agent.resumeDomain('mydomain.com');    // restore to rotation

Inbox

const inbox = await agent.inboxList({ limit: 20, include_body: true, since: '2026-06-01T00:00:00Z' });
// inbox.emails: [{ id, from, subject, received_at, thread_id, body?, attachments? }]

const email = await agent.inboxGet('email_id'); // full InboxEmail

inboxList and inboxGet are free. To reply, pass the email's id as reply_to_email_id to agent.email(...).

Pricing

Action	Cost
Send email	~$0.01/email (+ ~$10 one-time first domain provisioning)
Inbox list/get	Free

Errors

ContentBlockedError (policy), ValidationError (bad address/body), ToolError (e.g. no_sending_domain). See the oneshot skill for the full set.

oneshot-email

OneShot — Email

Send email — agent.email(options)

Send email — `agent.email(options)`