domain-authentication SKILL.md skillA
domain-authentication from chunkydotdev/email-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add chunkydotdev/email-skills/domain-authentication@git:20260330.54aae55Pins git:20260330.54aae55 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- chunkydotdev/email-skills
- Path
skills/setup/domain-authentication/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260330.54aae55, committed Mar 30, 2026
- First version recorded
- Mar 30, 2026
- Size
- 16,201 bytes
- Repository stars
- 7
- License
- MIT
Set up SPF, DKIM, and DMARC email authentication. Use when configuring a new sending domain, debugging spam/rejection issues, adding email providers, or preparing for Google/Yahoo/Microsoft bulk sender requirements.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Domain Authentication Set up SPF, DKIM, and DMARC so your emails actually reach the inbox. ## When to use this skill - Setting up email sending for a new domain - Emails are landing in spam or being rejected - Adding a new email provider or SaaS tool that sends on your behalf - Preparing for Google/Yahoo/Microsoft bulk sender requirements - Auditing an existing domain's authentication setup - Locking down a domain that doesn't send email ## Related skills - `email-warmup` - after authentication is in place, ramp sending volume gradually - `provider-setup` - choose and configure an email provider - `bounce-handling` - handle delivery failures and protect your reputation - `email-compliance` - legal requirements (CAN-SPAM, GDPR, unsubscribe) --- ## The authentication stack Three protocols work together. All three are required - not optional - for any domain sending email in 2025+. | Protocol | What it does | DNS record type | |----------|-------------|-----------------| | SPF | Declares which servers can send email for your domain | TXT on domain root | | DKIM | Cryptographically signs each message to prove it wasn't tampered with | TXT or CNAME on selector subdomain | …
Read the whole file at its exact version.
How to install
mdr add chunkydotdev/email-skills/domain-authentication@sha256:3b39c8c4b0ef6664The line at the top of this page pins the label git:20260330.54aae55, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_sp34up2zwchqivdn)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, all committed on Mar 30, 2026. Its first recorded version is graded C and its latest A.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260330.54aae55 latest | 2026-03-30 | 54aae55 | 16,201 B | A | view · diff |
| git:20260330.c9b6a00 | 2026-03-30 | c9b6a00 | 15,922 B | C | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (16201 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
chunkydotdev/email-skills · 7 stars · license MIT · pushed 2026-10-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_sp34up2zwchqivdn GET https://markdownregistry.com/api/v1/resolve?ref=chunkydotdev/email-skills/domain-authentication GET https://markdownregistry.com/api/v1/blob/3b39c8c4b0ef666442b7f877ab512f47b054d2db731a78ab3d100888641faa8a
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.