The box's existing service-account domain-wide-delegation grant already includes
gmail.compose, which authorizes users.messages.send — verified 2026-06-15 by a
token-mint probe and a live messages.send to grant. So CRM-originated mail can
send through the account that already powers email capture: no SMTP account, no
app password, no admin change.
- backend/email_integration/gmail_send.py: send_via_gmail() impersonates a
domain user and POSTs users.messages.send (reuses credentials.py + the compose
scope; mirrors compose.py's REST pattern).
- backend/digest_mailer.py: send_digest() prefers Gmail DWD when enabled, falls
back to smtp_send otherwise. Sender = CRM_DIGEST_SENDER else first active admin.
- server.py: the admin test endpoint now routes through digest_mailer (so the
Settings button sends via DWD on the box with zero SMTP config). Recipient
restriction to the admin set and no-leak error handling preserved.
- test_gmail_send.py: build/send + transport routing (provider + urlopen faked).
19/19 backend green; s9pk typechecks.
SMTP (v75) stays as the fallback transport. Send-path decision + scope finding
recorded in ROADMAP.md and AGENTS.md.
Keysat