Cold Email Agent.
Sends personalized cold email at scale, paced to look human, never double-sends.
BuildEmail subflow: per-lead company research and personalized generation.
SendEmail subflow: branches by sender identity and POSTs to the right mailer.
End of run
Personalized cold emails land in real prospects’ inboxes, sent from the correct sender’s identity, with status written back to the source-of-truth Google Sheet so the next run never double-touches the same lead.
The agent ran ten times a day, Monday through Friday, 9am to 6pm sharp, for six months as the outbound engine, 1.2k runs deep, 26 published versions, $0.05 a run, 35 seconds end-to-end. The scheduled cadence has since wound down to make room for hand-crafted messaging, but as a large-scale outreach tool it held up.
Challenges it solves
Two senders, one pipeline. Leads are owned by one of two senders. Each run categorizes leads by owner, fetches the matching OAuth token, and sends from that identity, same playbook, two voices, zero crossed wires. This can scale up to over 100+ senders.
Per-lead personalization without a research analyst.
BuildEmail.flow extracts the company from each lead, runs a
fresh Google search for current context, and writes the email
with that context baked in. No mail-merge clichés, every send
references something current about the recipient’s company.
Don’t look like a bot. A randomizer node staggers send timing inside each hourly window so a thousand emails don’t leave the server at exactly :00:00. Sends are paced, ten cycles per day, not one giant blast, to keep deliverability and sender reputation intact.
Never double-send. A Normalize & Gate 48h function checks
every recipient against recent send history and silently drops
anyone who’s been contacted in the last 48 hours, regardless
of which sender touched them.
The Google Sheet as the only UI. No CRM, no admin dashboard. Leads in, status out, A:M columns, read on every run, updated on every send. Whoever owns the campaign edits a sheet; the agent does the rest.
Under the hood
Three workflows wire it together. Main.flow is the
orchestrator: fetch sheet, process, categorize, bucket leads by
owner, then for each owner fetch the matching auth token and
call BuildEmail.flow (extract company, Google search,
generate personalized email, queue) and SendEmail.flow
(format, branch by sender, HTTP POST to the right send
endpoint). Status updates land back in the same sheet before
End.
Built on Claude 3.7 Sonnet for the generation step; everything else is deterministic JavaScript or HTTP.
Example output, a real cold email the agent sent.
