Let me show you how I turned every new subscriber into a researched, qualified, personally-pitched sales lead…without writing a line of code
Last week I created this agent, and since you are here, here are some AI agents I have built before:
🚀 How I Built an AI Agent to Create Content for Your Brand.
🚀 How I Built an AI Agent to Research Content for Your Business
🚀 How I Built an AI Agent to Create Authoritative Social Media Content for Your Brand
And today, this is something very special for me…
Every time someone subscribes to your Substack, something happens. And then… nothing.
You get a notification. Maybe you glance at their profile if you’ve got a spare thirty seconds. Then you move on, because you’ve got fifteen other things pulling at you today, and “go research my new subscriber” isn’t one of them.
Here’s the part that stings: Some of those subscribers are exactly who you’d want to pitch. Founders. People who’ve raised a round. People with a live product, a landing page, real budget, real buying intent. They subscribed to you. They’re already warm. And you’ll never know it, because manually researching every new subscriber doesn’t scale past about subscriber number three.
So I stopped trying to do it manually.
I built an agent that catches the subscriber, researches them, decides if they’re worth pitching, writes the pitch in my own voice, sends it, and follows up if they go quiet..
I didn’t write a line of code. I didn’t even build a flowchart. I built the entire thing by talking to it, in plain English.
This week I’m showing you exactly what I built, how it works end to end, and what it’s already done in the wild.
Paid subscribers get the full build…the fold...the exact prompts I used for every stage, the sheet structure, and how I built the “skill” that actually writes the pitch, so you can build the same thing around your own offer.
Meet the Subscriber Pitch Agent
Here’s the plain-English version:
It’s five agents, chained together, that turn “someone subscribed to my Substack” into “a qualified lead got a personal pitch and a follow-up sequence”…with a human (me) only touching it at one deliberate checkpoint.
Stage 1 — Catch the subscriber.
Substack sends a “New free subscriber to…” email to my Gmail every time someone joins. The agent watches for it, pulls the subscriber’s email and Substack profile link out of the email body, and logs it in a spreadsheet.
Stage 2 — Qualify the Person
Once a day, the agent goes back through anyone it hasn’t researched yet, visits their Substack profile, pulls their X, LinkedIn, and website links, and researches them..based my customer profile. If they clear the bar, they move to a “Prospects” list. If not, they’re just... a subscriber. No harm done.
Stage 3 — Draft the pitch, only when I say so.
This is the one place I stay in the loop on purpose. Nothing gets written up for send until I personally mark a prospect ready. When I do, the agent researches them further and drafts a fully personalized cold email…plus four follow-ups…using a “skill” I built specifically to write these pitches in my voice.
Stage 4 — Send it, once, cleanly.
Once I approve a draft, the agent sends the first email only (the follow-ups stay in reserve), grabs the email thread ID so it can track replies, and logs the send time.
Stage 5 — Follow up without me lifting a finger.
Every day, the agent checks if any sent prospect replied. If they did, it stops the sequence immediately…no awkward follow-up after someone already responded. If they didn’t, it sends the next follow-up on a set cadence, and gives up cleanly after five days.
That’s it.
So, why this…
This isn’t a “look what AI can do” toy. It’s a warm outbound channel that was sitting inside your subscriber list the whole time, doing nothing, because researching and personalizing outreach one person at a time is exactly the kind of task that eats your week and never gets prioritized.
You don’t need a sales team to have a lead qualification and outbound process. You need a system that runs the boring, repeatable steps…catch, research, qualify, draft, send, follow up…so the only decision left for you is the one that actually needs a human: is this pitch worth sending, yes or no.
The Real output (full agent workflow)
1. New subscriber hit the inbox
2. Add a new row to the Google Sheet
3. Run the qualification process, based on my ICP, once done, I get an email like this: 👇
4. Updated the Prospect Sheet with Email Draft to approve
5. Approve by changing the status to “Ready to Send Email”
6. Send the email
7. Follow-ups
That’s the whole system.
Now you may ask this:
Q: What if the agent can’t confidently tell if someone’s a good fit?
A: Build your qualification criteria to fail closed…if the research can’t verify a signal, it should not count in the prospect’s favor. It’s better to miss a borderline lead than to pitch someone based on a guess.
Q: Won’t this just spam people?
A: Only if you let it. The one deliberate gate in this build…Step 3…exists specifically so no email leaves your inbox without you personally reviewing the fit and approving the send. Automate the research, not the judgment call.
Q: What stops it from double-sending?
A: Two things…Step 3’s anti-loop check (won’t re-draft a row that’s already drafted) and Step 4’s skip condition (won’t send if ThreadID is already set). Build both checks in explicitly; don’t assume the platform handles it for you.
Let’s Build Step by Step:
Paid subscribers get the entire build, copy-paste ready:
The exact prompt I used for every one of the five agents, word for word
The exact Google Sheet column structure for both tabs
The real gotcha I hit (a silent permissions failure) and the one-line fix
How I built the pitch-writing “skill” itself…the actual instructions I gave it…plus a blueprint so you can build your own around any offer.
The full, real output by showing what happens really when I run this. (Actual case)
How to customize every stage for your own offer, audience, and qualification bar
If you’re building an audience and you’ve never turned a subscriber into a sales conversation without doing the research yourself, this is the exact system.
