Why AI Needs Priming Before It Writes a Single Word
If you ask an AI model to write a post-purchase email without context, you will get generic, robotic fluff. It will fill the email with buzzwords, exaggerated enthusiasm, and fake sincerity that your customers can spot immediately.
Getting decent copy out of ChatGPT requires a systematic priming sequence. You need to feed it your brand identity, product details, and target audience before you let it script a single subject line. In my books, an AI model should only ever produce version 1 of your copy, which a real copywriter then refines.
That is not optional.
Feeding Your Store Context and High-Margin Products
The first step is teaching the model who you are. You give it your exact website URL and prompt it to analyse your product catalogue, target demographic, customer reviews, and general tone of voice.
Here is something many brand owners miss: the model only knows what is publicly visible on your site. If your website highlights low-margin items as bestsellers, the AI will default to pushing those products.
- Define top performers manually: Feed the prompt direct links to the items with your strongest margins rather than just relying on site popularity.
- Include recent reviews: Direct the model to crawl real customer testimonials so it understands how your buyers actually speak.
- Run a fact-check prompt: Explicitly ask the AI to verify whether the product claims it gathered are accurate before moving forward.
Setting Strict Rules Before You Script
Once the model understands the brand, you must give it strict layout parameters. You need to outline how subject lines, body copy, and sign-offs should be formatted.
You must also include one critical instruction: tell it not to write the emails yet. AI models love to jump ahead and dump half-baked copy into the chat before you have defined the actual objective of the flow.
Tell the model to research standard post-purchase thank you flows and wait for your command. This keeps the conversation memory focused strictly on execution when you start the scripting phase.
Scripting Email 1A: The First-Time Buyer Note
My post-purchase thank you flows are deliberately different from what most agencies build. In this initial flow, I do not cross-sell or upsell anything. (Upsells belong in your fulfilled order flow once the customer actually has the product in hand).
Email 1A is a 100% plain text email sent from the founder. It is designed purely to build brand loyalty and show genuine appreciation to someone who just placed their first order.
Because you primed the model with your founder's name and brand voice, it will spit out a concise, grounded personal note. It acknowledges the purchase, explains why their support matters to an independent business, and signs off cleanly without aggressive promotional links.
Scripting Email 2A: Acknowledging the Second Purchase
Treating a repeat buyer like a first-time customer is a mistake. In Klaviyo, we use conditional trigger splits to separate first-time buyers from customers placing their second or third order.
For Email 2A, prompt the model to adapt the founder email specifically for someone placing their second order. The message needs to reflect that returning trust.
It takes roughly 30 seconds for the model to rewrite the message around loyalty rather than introduction. The copy should explicitly say that coming back for a second order proves real trust in the product, which hits far harder than a generic confirmation receipt.
The Mandatory Copywriter Review
Even with the best prompts in the world, AI will occasionally sneak in terms your brand would never use. It might slip in words like "community" or "journey" when your actual tone is understated and direct.
Take the AI-generated draft, drop it into your flow document, and have your team give it a thorough pass. Strip out the AI-isms, adjust the rhythm of the sentences, and make sure it sounds like a human sat down and typed it.
Using prompts this way saves about 80% of the initial writing time. It gets you to a solid first draft instantly, leaving your copy team to focus solely on nuance and polish.
Final Thoughts
AI will not replace a sharp copywriter, but it will eliminate the blank-page problem. When you prime the model with accurate product margins, customer reviews, and strict formatting rules, you get clean post-purchase drafts in minutes. Use it to build your baseline, split your first-time and repeat buyers, and always edit before hitting publish.
Next Steps
If you want automated post-purchase flows built, segmented, and optimised directly inside your account, explore our Email Automations service.
