skills / marketing

copywriting

what it does

When the user wants to write, rewrite, or improve marketing copy for any page, including homepage, landing pages, pricing pages, feature pages, about pages, or product pages. Also use when the user says "write copy for," "improve this copy," "rewrite this page," "marketing copy," "headline help," "CTA copy," "value proposition," "tagline," "hero section copy," "this copy is weak," "this sounds like AI," "AI slop," "make it sound human," or "help me describe my product." Drafts never use AI tells like "it's not X, it's Y" reveals, "no X, no Y, no Z" lists, or sentences that trail into extra comma clauses. For email copy, see emails. For popup copy, see popups. For editing existing copy, see copy-editing. For the offer underneath the copy (bonuses, guarantees, value framing), see offers. Claims must be supportable, and a declined claim names the evidence that would unlock it. Diagnoses the input first (blank brief, real voice, or point edit) and changes only what it calls for.

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.

“Write a homepage hero (headline, subhead, CTA) and a short launch post for X for our Shopify inventory app. It installs from the Shopify App Store in one click, needs no signup form or credit card, and runs low-stock alerts, reorder emails, and supplier purchase orders off the product and sales data the store already has, so there's nothing to import.”

with the skill
**Diagnosis:** A. The brief is a feature list with no existing voice, so I built the angle from it. The strongest fact is that it runs on data the store already has, so the headline leads there. I used only what you stated. ## Homepage hero **Headline** Restock from the sales data your store already has **Subhead** Install from the Shopify App Store in one click. [App name] reads your products and sales, sends low-stock alerts and reorder emails, and creates supplier purchase orders. **CTA button** Install from the Shopify App Store **Microcopy under button** No credit card required. ## Launch post for X > [App name] is live on the Shopify App Store. >
Show the rest (23 more lines)
> It reads the product and sales data your store already has, then sends low-stock alerts, reorder emails, and supplier purchase orders. Install is one click and there's nothing to import. > > No credit card required. [link] ## Annotations - **Headline:** Passes the "Now you can" test ("Now you can restock from the sales data your store already has"). A competitor can't copy it unless their app also needs no import. - **Subhead:** The three features are a real list of three, so I kept them together. "One click" is in the subhead because it answers "how much work is this?" right after the headline. - **Sign-up and card:** I turned "no signup form" into "install in one click," since the install is the signup. "No credit card required" appears once, next to the button, so the absences aren't stacked. - **X post:** No hashtags, emoji, or hype. The first line gives the news, the second says what it does, and the third gives the link. ## Headline alternatives - **Option A:** Low-stock alerts and purchase orders, built from the data you already have. This is more literal and names two features, but it's longer. - **Option B:** Reorder before you sell out. This is shorter and speaks to the pain, but a competitor could use it unchanged. Use it only if you pair it with the subhead above. ## Needed from you - `[NEED: app name]` - `[NEED: store link]` for the X post. - `[NEED: pricing]` Your brief says no card is required, but not whether the app is free, has a trial, or has a free tier. I avoided "free" in the CTA. If it's free or has a trial, "Start free" or "Try it free for [X] days" would convert better. - `[NEED: visual]` A short screen recording or screenshot of a low-stock alert turning into a purchase order would add more to the X post than any copy change. - **Proof, if any exists.** Install counts, review ratings, or merchant quotes would go in a line below the hero. I haven't written any because none were supplied.
without
## Homepage hero **Headline:** Inventory management that runs on the data you already have **Subhead:** Install in one click and get low-stock alerts, reorder emails, and supplier purchase orders, all built from your existing products and sales. No signup form, no credit card, nothing to import. **CTA button:** Add to Shopify **Microcopy under the button:** Free to install from the Shopify App Store. No credit card required. *(Only keep "free to install" if it's accurate. Otherwise use "No signup. No credit card. Nothing to import.")* **Alternate headlines:** - Never run out of stock, and never set anything up - Low-stock alerts, reorder emails, and POs. Installed in one click. - Your store already has the data. Now it can act on it.
Show the rest (23 more lines)
--- ## Launch post for X > Launching [App Name] 🚀 > > Shopify inventory, minus the setup: > > → One-click install from the App Store > → No signup, no credit card > → Low-stock alerts, reorder emails + supplier POs from the product and sales data you already have > > Nothing to import. [link] That's roughly 260 characters, but check the count once your app name and link are in. **Shorter alternative:** > Most inventory apps want a signup, a credit card, and a CSV import before they do anything. > > [App Name] wants one click. It reads your existing Shopify data and handles low-stock alerts, reorder emails, and supplier POs. [link] If you share the app name, pricing model, and who it's for (e.g., small DTC brands vs. larger merchants), I can tighten the copy further.

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

feature-section

“Write a short feature section for Pinpoint's new scheduled reports feature.”

hero-invoicing

“Write the hero section for Tallybook's homepage: headline, subheadline and button text.”

rewrite-headline

“Rewrite this headline: 'An Innovative AI-Powered Platform for Streamlined Business Operations'. It's for a tool that helps small businesses send invoices and collect payments.”

signup-page

“Write the copy for the signup page of our free tool that checks whether your email will land in spam.”

why-switch-section

“Write a 'Why teams switch' section for Ledgerline's homepage, about 120 words.”

The creator’s own tests

creator-1

“Write homepage copy for a SaaS tool that automates employee onboarding. Target audience is HR directors at mid-size companies (200-2000 employees). Main differentiator is that it integrates with all major HRIS systems and cuts onboarding time from 2 weeks to 2 days.”

creator-10

“Can you make this homepage hero better? I wrote it myself and it feels rough. Headline: Your agency doesn't need another dashboard. It needs to get paid. Subhead: We got sick of chasing clients for money, so we built the thing that does it for us. Invoices go out when the work ships. Late payers get nagged. You get your evenings back. CTA: Try it free”

creator-2

“Rewrite this headline: 'An Innovative AI-Powered Platform for Streamlined Business Operations' — it's for a B2B SaaS tool that helps small businesses manage invoicing and payments.”

creator-3

“i need copy for my pricing page. we have three plans: starter ($29/mo), pro ($79/mo), business ($199/mo). it's a social media scheduling tool for marketers”

creator-4

“Write copy for our About page. We're a 3-person startup that built a developer tool for database migrations. Founded because we kept losing data during migrations at our last jobs. Tone should be professional but human.”

creator-5

“Can you improve this CTA? We currently have 'Learn More' on our feature page for our analytics dashboard product.”

creator-6

“Write me a 5-email welcome sequence for new trial users of our project management tool.”

creator-7

“Review this copy and tell me what's wrong: 'We are extremely excited to announce our revolutionary, cutting-edge platform that will totally transform how businesses optimize their workflows! Sign up now!!'”

creator-8

“Write above-the-fold copy for a calendar scheduling tool. Our differentiator is that the recipient gets to overlay their own calendar on the invite, so picking a time feels fair to both people instead of one-sided. Same product needs to work for indie founders AND for enterprise ops teams.”

creator-9

“Write a homepage hero (headline, subhead, CTA) and a short launch post for X for our Shopify inventory app. It installs from the Shopify App Store in one click, needs no signup form or credit card, and runs low-stock alerts, reorder emails, and supplier purchase orders off the product and sales data the store already has, so there's nothing to import.”

Install

Download the .zip and unzip it. Put its files, in a folder named copywriting, 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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