The moment the app says “check your email”, most automation stops. This does not.

When a project enables the mailbox capability, a mail catcher runs beside the application in its environment and the app's SMTP settings point at it. The agent gets the mail as tools: wait for a message, read it, search, and follow the link or code it contains, in the same browser session.

In the dashboard: Projects
Feature specs: 37

agentSubmitted the participant email on /register. The page says "Check your inbox for a sign-in link". Waiting for the message.
toolwait_for_email({ to: "participant+7f2a@qa.test", subject_contains: "Your sign-in link", timeout_s: 60 })
→ { id: "m_41", from: "noreply@jade.events", received_at: "…12:04:31Z", links: ["https://…/auth/magic?token=…"] }
toolbrowser_navigate("https://127.0.0.1:41733/auth/magic?token=…")
agentLanded on the participant dashboard as Jordan Ruiz. The welcome banner and the event card are present. Continuing with step 4.

What it looks like in a run.

The excerpt is the shape of a real transcript: the agent explains what it sees, calls a mail tool, gets back the message with its links already extracted, and navigates. Nothing is mocked in the app; the email really was sent and really was read.

Tool	Does
`wait_for_email`	blocks until a message matching recipient and subject arrives, or times out
`get_email`	returns one message with text, HTML, links and codes parsed out
`search_emails`	lists recent messages by recipient, sender or subject
`send_email`	sends into the app for inbound-mail flows (a support inbox, a reply-to)

Flows this unlocks.

Magic-link sign-in: request the link, read it, land signed in, continue the test.
One-time codes: the code is parsed from the message and typed into the form.
Invitations: an admin invites a colleague; the agent accepts as the invitee from the email.
Verification and receipts: assert the confirmation mail arrived with the right event, dates and reference, not just that the page said so.
Rendered email: open the HTML body in a tab and screenshot it, so the recording shows what the recipient would see.

Project → isolated environment → mailbox

mailbox:
  enabled: true
  # Injected into the app's boot env by the platform:
  SMTP_HOST: 127.0.0.1     SMTP_PORT: 1025
  EMAIL_DOMAIN_ALLOWLIST: qa.test    # apps that allow-list recipients need this

# The agent's own test addresses use a plus-tag so parallel runs never
# read each other's mail:  participant+<job-id-prefix>@qa.test

Where it stops today

The mailbox is part of an isolated environment. A project that tests a fixed URL has no captured mail unless that deployment already points at a catcher the platform can read.
Mail the app sends through a third-party API (rather than SMTP) is only captured if the app can be pointed at the catcher's SMTP port in test configuration.
The catcher is Mailpit. Its readiness probe is known to fail on the docker backend in local development; it works on the cluster and native box backends.
Inbound mail (send_email) reaches the app only if the app polls or receives from the catcher; most do not, and the seeded examples that do are Jade's support inbox.