About cold-email
A skill for drafting concise, signal-based cold emails and follow-up sequences. It guides users through sender setup, recipient research, message structure, and checks before sending.
Key features
- 01Sender authentication and warmup guidance
- 02Collects recipient, credentials, ask, and signal
- 03Under-80-word email structure
- 04Outreach-specific email guidance
- 05Subject line and voice recommendations
- 06Follow-up sequence and verification checklist
Use cases
- 01Drafting investor or partnership outreach
- 02Writing job or consulting inquiries
- 03Preparing advice or mentorship requests
- 04Checking email copy and sender setup
Install
Copy the command and run it in a terminal.
npx skills add https:/After installing, type/cold-emailin Claude Code to confirm it loaded.
Bundled filesreferences/guide.md
Details
From the project READMEWrite cold emails that get responses. Ultra-short, signal-based, specific. Under 80 words — everything else is noise.
Phase 0: Sender Setup (Do Once)
Before sending a single cold email, your domain needs to pass authentication. Gmail, Yahoo, and Microsoft all reject non-compliant senders.
Required DNS records:
- SPF —
v=spf1 include:youresp.com ~all(authorizes your sending server) - DKIM — 2048-bit key, set up through your ESP (Resend, SendGrid, Postmark)
- DMARC — minimum
v=DMARC1; p=none; rua=mailto:[email protected]
Domain warmup:
- New domain: start at 20–30 emails/day, ramp over 4–6 weeks
- Production limit: 50–100 emails per mailbox per day, never more
- Scale with multiple warmed mailboxes (3–5) rather than volume per mailbox
Health targets:
- Bounce rate: under 2% (above 5%, most ESPs suspend you)
- Spam complaint rate: under 0.1% (Gmail hard limit is 0.3%)
- If open rates are below 30%, the problem is infrastructure, not copy
Phase 1: Gather
Before writing, you need four things. Ask for anything missing:
- Recipient — Name, role, company
- Your credentials — Past wins, numbers, notable affiliations
- Your ask — What you actually want
- Signal — A specific, recent, verifiable event about the recipient
Signal types ranked by reply rate:
- Leadership change (new role in past 90 days): 14–25% reply rate
- Funding round: 12–20% reply rate
- Hiring surge (10+ open roles in their function): 10–18% reply rate
- Technology adoption (just switched tools): 8–15% reply rate
If no signal exists, use a specific piece of their work — a post, a talk, a product decision. Generic admiration ("I've been following your work") is not a signal.
Phase 2: The Formula
Every email follows this structure. No exceptions.
Subject: [Signal reference or direct question, under 45 chars]
Hey [FirstName],
[Signal + implication — prove you know their specific situation] (1 sentence)
[Your credibility with concrete details] (1 sentence)
[Single, time-specific ask] (1 sentence)
[Name]
Under 80 words. One CTA. No signature block. No "Best regards." No "I hope this email finds you well."
Phase 3: Email Types
Auto-select based on context. Formula stays the same — emphasis shifts.
| Type | Signal to use | Credibility to lead with |
|---|---|---|
| Investor outreach | Funding round they led, portfolio company they backed | Traction numbers, revenue, growth rate |
| Advice / Mentorship | Recent talk, article, or decision they made | Specific situation that mirrors what they solved |
| Job / Internship | Company news, new product, open role | One concrete result with numbers |
| Partnership | Their recent launch, expansion, or gap | Your users, revenue, or relevant customer |
| Paid consulting | Their specific expertise applied to your problem | Offer to pay upfront + tight scope |
Phase 4: Subject Lines
What works:
- Signal reference:
[Company]'s Series B — quick thought - Direct question:
How is [Company] handling [specific challenge]? - Mutual connection:
[Name] said I should reach out - Under 45 characters for mobile
What's dead:
- "Quick question" — one of the two most overused cold email subjects in 2026
- "Following up" — same
- Fake threading:
RE:orFW:on a first email - Anything with "free," "guaranteed," "limited time" (triggers spam filters)
Numbers in subject lines get 113% higher open rates. Use them when you have them: Saw [Company] posted 12 SDR roles
Phase 5: Voice
DO:
- Lead with the signal — first sentence proves situational awareness
- State credentials with numbers:
$2M ARR,backed by a16z,ex-Stripe - Make the ask time-specific:
15 min this Thursday?notgrab coffee sometime - Randomize send times — 3–8 minute intervals between emails, not batch sends
- Send Tuesday–Thursday mornings (Thursday 9–11 AM has highest open rates)
DON'T:
- Generic compliments: "I admire your work" with nothing specific
- More than one ask per email
- Long paragraphs about your background
- Emails over 80 words (2.4x lower reply rate vs. 50–125 words)
- Being apologetic for reaching out
Phase 6: Follow-Up Sequence
58% of replies come from the first email. But a sequence improves total response by 50%+.
Email 1 → follow up after 2–3 business days
Email 2 → follow up after 3–4 business days
Email 3 → follow up after 5–7 business days
Email 4+ → follow up after 7–14 business days
Follow-up template:
Subject: Re: [original subject]
Hey [Name],
Bumping this — still think [specific reason this is relevant to them].
[Name]
4–7 emails is the optimal sequence length. Stop if they ask you to.
Verify
[ ] Under 80 words
[ ] Opens with a specific, verifiable signal — not generic admiration
[ ] Credibility includes a number or a name
[ ] Single ask with a specific time
[ ] Subject under 45 characters, no spam trigger words
[ ] No "quick question", "following up", fake RE:
[ ] Casual — you'd send this to a colleague
[ ] SPF + DKIM + DMARC set up on the sending domain
[ ] Sending under 100 emails/day per mailbox
See references/guide.md for real examples that got replies from Evan Spiegel, Mark Cuban, and Elon Musk — plus templates by situation and advanced tactics.