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.
npx skills add AlexisMarasigan/coldoutboundskills --skill email-deliverability-auditgit clone --depth 1 https://github.com/AlexisMarasigan/coldoutboundskillsWrote 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.
[](https://agentmods.dev/skills/alexismarasigan/coldoutboundskills/email-deliverability-audit)<a href="https://agentmods.dev/skills/alexismarasigan/coldoutboundskills/email-deliverability-audit"><img src="https://agentmods.dev/badge/skills/alexismarasigan/coldoutboundskills/email-deliverability-audit/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.
<a href="https://agentmods.dev/skills/alexismarasigan/coldoutboundskills/email-deliverability-audit"><img src="https://agentmods.dev/badge/skills/alexismarasigan/coldoutboundskills/email-deliverability-audit.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00101 | $0.02710 |
| Opus 5.5 | $0.00040 | $0.01084 |
| Sonnet 5.5 | $0.00020 | $0.00542 |
| Haiku 4.5 | $0.00010 | $0.00271 |
Grade A, and why
email-deliverability-audit 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 2mo 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.
This is a copy
100% identical to email-deliverability-audit — 111 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 228 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Email Deliverability Audit
If your positive reply rate is dropping and you don't know why, start here. Most of the time the problem is deliverability — your emails aren't reaching inboxes. This skill tells you what's broken.
What it checks
| Layer | What | How |
|---|---|---|
| DNS auth | SPF, DKIM, DMARC present on each sending domain | dig commands |
| Inbox health | Warmup status, reputation, blocks, connection failures | Smartlead email-accounts API |
| Volume health | Daily sent trending, capacity utilization | Smartlead analytics |
| Send + reply rate per inbox | Sent count, reply count, reply rate % over lookback period | Smartlead campaign analytics |
| Bounce rate | Per-inbox and per-domain bounce rate over last 30 days | Smartlead campaign analytics |
| Spam placement | Real inbox-vs-spam test via Smartlead Smart Delivery | optional |
The 1% rule — core domain-health threshold
A healthy domain should have an overall reply rate of at least 1% after 200 emails sent.
Below 1% after 200+ sends is a red flag — something is broken. The audit explicitly checks this and flags any domain or inbox that:
- Has sent ≥200 emails in the lookback window
- Has an overall reply rate <1%
Possible causes (the audit's "root-cause suggestions" try to pinpoint which):
- Emails landing in spam (run the spam placement test)
- Domain reputation damaged (check DMARC reports, reconsider domain age)
- Copy is broken (manually review for vague CTAs, generic openers, or em dashes; re-run
/spam-word-checker) - List is cold / wrong ICP (check bounce rate — if >3%, list is the problem)
- Inbox hasn't warmed enough (check warmup status)
Below 200 sends: too early to judge. The rule needs sample size.
When to use
- Reply rate dropped by >30% week-over-week → run the full audit
- Bounces spiked above 2% → run auth + spam-placement checks
- Before scaling a campaign (make sure infrastructure is ready)
- Monthly as routine hygiene
- When taking over a Smartlead account you didn't set up
What ships with it
5 files 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.
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.
- 2mo ago First seen · 228 lines · 101 tokens per session scan A e3f675d6f8a3
email-deliverability-audit is a skill published in the GitHub repository AlexisMarasigan/coldoutboundskills (5 stars, last pushed 6mo ago), licensed MIT. It adds 101 tokens to every session and 2,710 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to email-deliverability-audit, differing in 111 lines, and is treated as a copy.
email-deliverability-audit compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| email-deliverability-auditAlexisMarasigan/coldoutboundskills | Skill | 5 | 6mo ago | MIT | A | 101 | Claude Code |
| imagegenopenai/codex | Skill | 133k | yesterday | Apache-2.0 | A | 113 | Codex |
| playwright-climicrosoft/playwright | Skill | 99k | yesterday | Apache-2.0 | A | 19 | Claude Code |
| local-ai-agentsmicrosoft/ai-agents-for-beginners | Skill | 79k | 4d ago | MIT | A | 200 | Claude Code, Codex |
| systematic-debuggingobra/superpowers | Skill | 313k | 3d ago | MIT | A | 21 | Claude Code |
| next-cache-components-adoptionvercel/next.js | Skill | 143k | today | MIT | A | 95 | Claude Code |
| next-partial-prefetching-adoptionvercel/next.js | Skill | 143k | today | MIT | A | 103 | Claude Code |