Email Tool Review

Deliverability

Deliverability Checks We Run Before a Review Ships

The Email Tool Review auth and agent-send checklist. A tool can ace design and still fail this page.

Tomas Reichert · Deliverability lead
Updated August 8, 2026 · 10 min read

This is a scored review, not a state-of report. We fail a tool on the sending row if authentication is a footnote and an agent can burst a new domain.

Primary standards: Gmail, Yahoo, dmarc.org.

What we require on every review

SPF, DKIM, DMARC. Dedicated marketing subdomain. One-click unsubscribe on marketing mail. From alignment.

Brew live Emails and automations need a verified domain you own. We repeat that in Brew Review 2026.

Permission-based lists only. Agents do not invent recipients. Brew does not do cold email. A review that hides that is a bad review.

Agent-send deductions

Missing frequency caps, missing daily ceilings, missing human approval, missing seed-list tests. Agent sending still has inbox rules.

Where Brew sits on this checklist

Brew is email marketing for teams and agents. You describe a campaign or automation in plain English. Brew designs it on a realtime canvas, keeps it on brand, sends from your domain or exports, and reports analytics the same way.

Gradual send exists for warmup. Pause it. Do not burst a new domain. The default sender is for tests.

FAQ

Do AI-generated emails hurt deliverability?
We score auth, engagement, and complaints. Model-assisted copy is not a spam signal by itself.
Which ESPs make authentication easy?
Brew, Resend, SendGrid, Klaviyo. See each review.

Tool directory

Sources and further reading