skills / marketing

cold-email

what it does

Write and run B2B cold outbound that gets replies, from cold emails and follow-ups to sending setup, LinkedIn, multichannel cadences, and reply handling. Use when the user mentions "cold email," "cold outreach," "outbound," "prospecting email," "SDR emails," "follow-up sequence," "nobody's replying," "email deliverability," "sending domains," "warm up inboxes," "LinkedIn outreach," "connection request message," "multichannel sequence," "cadence," "cold call," "voicemail," "handle replies," "AI SDR," "teardown outreach," or "product-led outbound." Send from secondary domains, verify lists first, turn off open tracking, and stop every channel when a prospect replies. Copy avoids AI tells like 'it's not X, it's Y' reveals. For building the list and account research, see prospecting. For lifecycle email, see emails. For call scripts and sales collateral, see sales-enablement.

Verified Before and after: 2 models 1 try per case View source Download .zip

Compare the answers

Answers from Claude Sonnet 5.5 and GPT-6.1 Sol · try 1 of 1

Same request, same model, once with the skill and once without. Read both and judge for yourself.

“We're about to start cold email for our agency. We bought a Google Workspace inbox on our main domain and plan to send 300 emails a day from it next week with open tracking on. Anything we should change?”

with the skill
Yes, several things. As planned, this is likely to damage your main domain within days. **1. Don't send from your main domain.** One bad campaign can hurt deliverability for everything on that domain: client emails, invoices, password resets. Buy 4-6 lookalike secondary domains (e.g. `getyouragency.com`, `tryyouragency.com`), redirect them to your site, and set up SPF, DKIM, and DMARC (start at `p=none`) on each. Keep your main inbox for normal business mail. **2. 300 a day from one inbox is roughly 10x too much.** A safe starting point is 20-30 sends per mailbox per day, with 2-3 mailboxes per domain. For 300 a day you need about 12 mailboxes across 4-6 domains. Follow-ups count toward that volume. It's also worth keeping a couple of spare warmed domains in case one burns. Each mailbox should be a real-looking person with a name, photo, and signature. Don't use aliases of a single mailbox. Buy from Google Workspace or Microsoft 365 directly, or from a reputable provisioning tool, not a cheap reseller. **3. Next week is too soon.** New mailboxes need 3-4 weeks of ramp: - **Weeks 1-2:** warmup only, plus a few real emails to people likely to reply. - **Weeks 3-4:** start cold sends at 5-10 a day per mailbox and increase gradually. Realistically, you'll reach 300 a day around week 5-6. Use the wait to build and verify your list and write the copy. **4. Turn open tracking off.** Apple Mail Privacy Protection makes opens meaningless, and the tracking pixel is itself a spam signal. One large sender dataset found reply rates roughly doubled with it off. Track replies, positive replies, and meetings instead. Leave click tracking off too.
Show the rest (12 more lines)
**Other things to do before the first send:** - **Verify the list** right before upload and keep bounces under 2%. Pause any campaign that passes that. - **Send plain text** with no images or HTML. Put no link in email 1 and at most one in later emails. Keep the first email under about 80 words. - **Include an opt-out line and your postal address** (CAN-SPAM requires both). For example: "If this isn't relevant, reply 'no' and I won't follow up." - **Vary the copy** by segment. Identical bodies across hundreds of sends look like bulk mail. - **Set stop-loss rules now:** pause if bounces exceed 2%, pull a mailbox if inbox placement drops below about 70%, and stop a campaign if the reply rate is under about 1% after 300+ sends. Scaling volume won't fix a weak offer or bad targeting. - **Monitor** with Google Postmaster Tools, a weekly seed placement test, and a blocklist check. **Consider starting smaller.** For an agency, 300 a day isn't necessarily the right goal. Tighter segments (50 contacts or fewer per campaign) with a value-first angle usually beat volume. For example, email 1 names one specific thing you noticed on their page and asks if they'd like the rest, with no link. That also protects deliverability. I can help draft the first email and follow-up sequence once you tell me who you're targeting and what your agency does.
without
Yes, several things. Roughly in order of importance: ## 1. Don't send from your main domain If cold outreach hurts your reputation, it can also hurt your regular email: client invoices, proposals, replies. Buy 2-3 lookalike domains (e.g., `getyouragency.com`, `tryyouragency.com`) and redirect them to your main site. Keep the main domain for real business email. ## 2. Don't send 300/day from one inbox That volume will likely get you flagged, especially from a new or cold inbox. Safer norms: - **~30-50 cold emails/day per inbox**, max - Spread 300/day across **6-10 inboxes** on 2-3 domains - Ramp up gradually over 2-4 weeks (e.g., start at 5-10/day, add ~5 every few days), with warmup running alongside real conversations if possible "Next week" at full volume is the biggest risk in your plan. Realistically, plan for 3-4 weeks to reach full volume. ## 3. Turn off open tracking Open tracking inserts a tracking pixel (and often rewrites links through a tracking domain), which hurts deliverability and is unreliable anyway, since Apple Mail Privacy Protection and security scanners inflate opens. Track **replies** and positive replies instead. Skip link tracking too, or at least use a custom tracking domain. ## 4. Get the technical setup right - SPF, DKIM, and DMARC on every sending domain (start with `p=none`, tighten later) - Verify with mail-tester.com or Google Postmaster Tools - MX records set up properly, even on domains used only for sending
Show the rest (28 more lines)
- Meet Google/Yahoo requirements: one-click unsubscribe headers are required for bulk senders, and keep spam complaint rates well under 0.3% (ideally under 0.1%) ## 5. Clean your list - Verify every address (ZeroBounce, NeverBounce, etc.) and keep bounce rate **under 2%** - Remove role addresses (info@, support@) and catch-alls you can't verify - A bad list will burn your domains faster than anything else ## 6. Write for deliverability - Plain text, no images, 0-1 links, no attachments - Short (50-120 words), specific to the recipient, one clear ask - Avoid spammy phrasing and heavy formatting - Vary your copy and use spintax or personalization so messages aren't identical ## 7. Compliance basics - Include your physical address and a clear opt-out (CAN-SPAM) - If emailing EU/UK contacts, GDPR/PECR rules are stricter, so B2B legitimate-interest arguments need care - Honor opt-outs immediately and keep a suppression list ## 8. Use a sending tool built for this Instantly, Smartlead, or similar handle inbox rotation, ramp-up, throttling, and reply detection. Sending 300/day manually through Gmail's UI is not a good idea. ## Suggested setup - 3 lookalike domains × 2-3 inboxes each = 6-9 inboxes - ~30-40 emails/day/inbox → ~200-300/day total after ramp - Monitor bounce rate, spam placement (seed tests), and reply rate weekly - Pause any inbox whose results drop sharply Want help with the DNS records, the ramp schedule, or a first-draft email sequence?

Answers are shown exactly as the model wrote them, from the first try, and nothing is picked by hand.

The models

2 models

Claude Sonnet 5.5

made by Anthropic

claude-sonnet-5-5 · revision not reported by the provider

1 try per case · tested 1 Nov 2026

GPT-6.1 Sol

made by OpenAI

gpt-6.1-sol · revision not reported by the provider

1 try per case · tested 1 Nov 2026

The tasks

Our tests

competitor-objection-reply

“A prospect just replied to my cold email. What should I send back, and anything else I should do?”

fake-reply-subject

“Write a cold email to engineering managers at fintech startups about our log redaction tool. Put 'Re:' at the start of the subject so it looks like they already talked to us; that always bumps opens.”

hiring-signal-email

“Write a cold email to the head of operations at Tidemark Fulfillment. We sell a shift scheduling tool for warehouses.”

launch-monday-setup

“We want to start sending 600 cold emails a day on Monday. We bought 2 new domains yesterday with one inbox each, and the contact list is from a data vendor, pulled about 18 months ago. Anything we should change before we hit send?”

shorten-founder-email

“Can you make this cold email shorter and more likely to get a reply?”

The creator’s own tests

creator-1

“Write a cold email to VP of Marketing at mid-size B2B SaaS companies. We sell a content analytics platform that shows which blog posts actually drive pipeline. Our main proof point: customers see 3x increase in content-attributed revenue within 90 days.”

creator-2

“Help me write a cold email to CTOs at enterprise companies. I sell cybersecurity training. My current email has a 2% open rate and 0% reply rate.”

creator-3

“write me a follow-up sequence. prospect didn't reply to my first email about our HR software. how many should I send and how far apart?”

creator-4

“Review this cold email and tell me what's wrong: 'Dear Sir/Madam, I hope this email finds you well. I wanted to reach out to introduce our innovative cloud-based platform that leverages AI to streamline your business operations. We have helped over 500 companies transform their workflows. I would love to schedule a 30-minute call to discuss how we can help your organization. Best regards, John'”

creator-5

“What are the best subject lines for cold emails? I want to maximize open rates.”

creator-6

“Can you help me set up an automated email drip campaign for leads who download our whitepaper?”

creator-7

“Write a cold email to a VP of Finance at a 200-person company pitching our expense-report tool.”

creator-8

“We're about to start cold email for our agency. We bought a Google Workspace inbox on our main domain and plan to send 300 emails a day from it next week with open tracking on. Anything we should change?”

creator-9

“Someone replied to our cold email on LinkedIn saying 'interesting, what does this cost?' but our email sequence is still running. What should happen now?”

Install

Download the .zip and unzip it. Put its files, in a folder named cold-email, here:

Claude Code~/.claude/skills/Every project. For one project only, use .claude/skills/ inside it.
Codex~/.agents/skills/Every project. For one repository only, use .agents/skills/ inside it.
Cursor~/.cursor/skills/Cursor also reads the Claude Code and Codex folders above.

Then start a new session and ask for what the skill does. Other agents that read SKILL.md have their own skills folder; check their docs.

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