---
title: "Domain Audit Claude Skill for Cold Email Setup"
description: "A Claude skill that audits a sending domain before you use it. Grades SPF, DKIM, DMARC, MX, BIMI and MTA-STS and returns the fixes in order of impact."
url: https://warminboxes.com/skills/domain-audit
breadcrumb: "Home > Claude Skills > Domain Audit"
---
Claude skill

# Domain Audit

Is this domain set up correctly to send from?

A pre-flight check rather than a post-mortem. Hand it a domain you are about to send from and it grades the whole authentication setup, then puts the fixes in the order that actually matters rather than the order it happened to run them.

## What it runs

- **SPF** — The record, the recursive lookup count, and whether it breaks the 10-lookup limit

- **DKIM** — The key and its strength, sweeping the common selectors when you do not know yours

- **DMARC** — Policy, alignment and what each tag is actually doing

- **MX** — Where mail is routed and whether it matches the platform you think you are on

- **MTA-STS and BIMI** — The optional layers, mentioned only once the fundamentals pass

- **Blacklists and SURBL** — Whether the domain is clean before you start

- **Registration age** — Whether its history supports the volume you have planned

## What you get back

- A letter grade and a score out of 100

- The single biggest problem, first

- Every fix with the record to publish, generated rather than written from memory

- A note on what to watch if everything already passes

## Install it

One file, from GitHub. It calls the free WarmInboxes API, so there is no key and nothing to sign up for.

 mkdir -p ~/.claude/skills/domain-audit
curl -sL https://raw.githubusercontent.com/Huz-ai-fa/warminboxes-claude-skills/main/domain-audit/SKILL.md -o ~/.claude/skills/domain-audit/SKILL.md

[View it on GitHub →](https://github.com/Huz-ai-fa/warminboxes-claude-skills/tree/main/domain-audit)

## Then just ask

You do not name the skill. Its description tells Claude when it applies.

- "Audit the DNS on my new cold email domain"

- "Check SPF and DKIM for acme.com before I start sending"

- "I inherited this infrastructure, is the email authentication right?"

Every answer cites the check behind it, so anything Claude tells you can be re-run by hand. A clean result is reported clean, with nothing to buy.

[All Claude skills →](https://warminboxes.com/skills)

## Do it by hand

The same checks as free tools in a browser.

- [Deliverability Checker](https://warminboxes.com/deliverability-checker)

- [SPF Checker](https://warminboxes.com/spf-checker)

- [DKIM Checker](https://warminboxes.com/dkim-checker)

- [DMARC Checker](https://warminboxes.com/dmarc-checker)

## The other skills

One page each.

- [Inbox Checker](https://warminboxes.com/skills/inbox-checker) — Is this domain burned?

- [List Segmentation](https://warminboxes.com/skills/list-segmentation) — Who hosts the people on this list?

- [Infrastructure Planner](https://warminboxes.com/skills/infrastructure-planner) — How many mailboxes do I need, and what does it cost?