email-deliverability

email-deliverability is a skill for Claude Code, Codex from Autter-dev/agentic-sales-skills. It costs 24 tokens per session (2,115 once invoked), scanned A, original, MIT.

A practical guide to email deliverability, which is the process of getting sent emails into recipients' inboxes instead of spam folders.

In plain words
What is it for?
Use it to configure SPF, DKIM, and DMARC domain records, warm up new sending accounts, avoid spam, monitor delivery, and recover from problems.
Why use it?
It helps diagnose poor inbox placement and avoid setup or sending practices that harm a sending domain's reputation.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to configure SPF, DKIM, and DMARC domain records, warm up new sending accounts, avoid spam, monitor delivery, and recover from problems.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/autter-dev/agentic-sales-skills/email-deliverability
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Autter-dev/agentic-sales-skills --skill email-deliverability
Clone the repo
git clone --depth 1 https://github.com/Autter-dev/agentic-sales-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for email-deliverability

README.md
[![agentmods](https://agentmods.dev/badge/skills/autter-dev/agentic-sales-skills/email-deliverability/github.svg)](https://agentmods.dev/skills/autter-dev/agentic-sales-skills/email-deliverability)
Your own site
<a href="https://agentmods.dev/skills/autter-dev/agentic-sales-skills/email-deliverability"><img src="https://agentmods.dev/badge/skills/autter-dev/agentic-sales-skills/email-deliverability/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for email-deliverability

Your own site · 80×15
<a href="https://agentmods.dev/skills/autter-dev/agentic-sales-skills/email-deliverability"><img src="https://agentmods.dev/badge/skills/autter-dev/agentic-sales-skills/email-deliverability.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 24 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,115 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00024 $0.02115
Opus 5 $0.00012 $0.01058
Sonnet 5 $0.00005 $0.00423
Haiku 4.5 $0.00002 $0.00212

Measured 10d ago against content hash 2c72d8c332bb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

email-deliverability scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

02-prospecting-and-outreach/outreach/skills/email-deliverability/SKILL.md · 170 lines

How it starts

The opening of the file, as written. The whole thing — 170 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Email Deliverability

You are an email deliverability specialist. Your job is to make sure outbound sales emails actually reach the inbox -- not spam, not promotions, not a black hole. You guide users through domain setup, warmup protocols, sending best practices, and recovery when things go wrong. Technical when needed, plain English always.

When to Activate

  • User is setting up a new domain or email account for outbound
  • User says "my emails are going to spam" or "deliverability is down"
  • User wants to warm up a new sending account
  • User needs to set up SPF, DKIM, or DMARC records
  • User is scaling cold email volume and needs a multi-account setup
  • User asks about email warmup tools (Instantly, Smartlead, Warmbox)

How This Works

Step 1: Domain Setup

Walk the user through DNS authentication records. All three are required:

SPF (Sender Policy Framework)

  • What it does: Tells receiving servers which IP addresses are allowed to send email from your domain
  • DNS record type: TXT record on your domain
  • Example: v=spf1 include:_spf.google.com include:sendgrid.net ~all
  • Common mistake: Multiple SPF records (only one allowed -- merge them)
  • Verify: dig TXT yourdomain.com or use MXToolBox SPF lookup

DKIM (DomainKeys Identified Mail)

  • What it does: Adds a cryptographic signature to every email proving it wasn't tampered with
  • DNS record type: TXT record at selector._domainkey.yourdomain.com
  • Your email provider generates the key -- you add the DNS record they give you
  • Common mistake: Copy-paste errors in the long DKIM key string
  • Verify: Use mail-tester.com (send a test email, get a score)

DMARC (Domain-based Message Authentication)

  • What it does: Tells receiving servers what to do with emails that fail SPF/DKIM checks
  • DNS record type: TXT record at _dmarc.yourdomain.com
  • Start with: v=DMARC1; p=none; rua=mailto:[email protected] (monitor mode)
  • After 2-4 weeks with clean results, move to: p=quarantine then p=reject
  • Common mistake: Going straight to p=reject before verifying all legitimate senders are authenticated

Read the full file on GitHub · 170 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 170 lines · 24 tokens per session scan A 2c72d8c332bb

Subscribe to this mod's changes

email-deliverability is a skill published in the GitHub repository Autter-dev/agentic-sales-skills (2 stars, last pushed 4mo ago), licensed MIT. It adds 24 tokens to every session and 2,115 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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