Make AI-written marketing emails consistently good: have the AI draft 10 at a time, grade each A to D against your best past emails, feed the grades back and repeat until every draft scores an A, then re-test whenever you change the prompt: AI agent prompt
A Nov 3, 2026 AIPOST article describes a print-on-demand t-shirt brand (its Shopify dashboards show about $1.83M in 2025 sales) that runs four separate AI agents for support, email, design and ads. Its email agent is trained on a folder of the brand's top-performing past emails and a rubric (on-brand message, reuse of offers already tested). To fix inconsistent AI emails, the brand uses 'evals': the agent drafts a batch of 10, each gets a letter grade from A to D with feedback, Claude reads the grades and adjusts, and rounds repeat until outputs consistently hit A. Every later prompt change is benchmarked against the previous version before it goes live. Suggested campaigns then sit on a Suggested / Approved / Sent board and only go out after the owner clicks Approve. The brand does not name itself in the article, and the sales figures are one business's results.
The prompt
1. Put your 10-20 best-performing past emails (subject line, body, results) in one folder, plus a one-page rubric you write yourself: what an A email does (on-brand, one clear offer you've already tested, short) and what makes a D. 2. Ask Claude or ChatGPT: "Using these example emails and this rubric, draft 10 emails for [campaign, e.g. new listings this week / spring promo] for [audience]." 3. Grade each draft A to D yourself (or have a second chat grade them with the rubric and you spot-check), with one line on why. 4. Paste the grades back: "Here are the grades and reasons. Update your approach and draft 10 more." Repeat until most drafts are A. 5. Save the final instructions as your email prompt. Whenever you change even one sentence of it, re-run a batch of 10 and compare the grades with the last version before using it. 6. Nothing sends automatically: keep a simple Suggested / Approved / Sent list and approve each campaign yourself.
Fill in the blanks, then copy
This prompt has 2 [bracket]s to fill in. Type your details below and the prompt updates as you go. Your answers stay in this browser and are reused on other prompts with the same blanks. Nothing is sent to us.
Example values are fictional, just to show how a filled-in prompt reads. Replace them with your real details.How to use it
- Copy the prompt above.
- Replace every [bracket] with your own details (use the fill-in-the-blanks box above, which remembers your answers for the next prompt).
- Paste it into Claude or ChatGPT, your email platform, a spreadsheet or board for approvals and review the answer before you use it.
Works with: Claude or ChatGPT, your email platform, a spreadsheet or board for approvals
Real-world example: aipost.kr/posts/2026-11-03-tshirt-brand-four-ai-agents-operations/
Featured in: ChatGPT prompts for business email, replies and follow-ups
Before you use it: what to check
Already built into this prompt
- Nothing sends automatically: keep a simple Suggested / Approved / Sent list and approve each campaign yourself.
Check yourself
- Check every figure, price and total against your own records before anything is sent, posted or booked. A person approves refunds, discounts, payments and price changes.
- Read and edit the draft before it reaches a customer or goes public. If you later automate this prompt, start with "draft and notify me", not "send automatically".
- Check names, dates, numbers and any claim against your own source material before you use the answer. AI can misread or invent details.
Using an AI agent? Download this prompt as a SKILL.md agent skill with these checks built in, or get the .zip for Claude.ai. How to install skills.
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