I gave my landing page to an AI skill built to improve conversions and asked what was wrong with it. It caught the empty headline and the missing trust signals in seconds. But then it stopped and asked me who the page was even for. That pause taught me more than the fixes did.
A marketing skill is only as sharp as what it knows about your product. Feed it nothing and you get a checklist any senior marketer could recite. Feed it your real audience and it changes its mind about what matters. So I installed the collection and tested it like a tool for client work.
What it is
Marketing Skills is a set of marketing instruction files for Claude Code and other coding agents, built by Corey Haines, who ran growth at Baremetrics. It's popular, at about 41k stars. Each skill is plain markdown that teaches the agent one job, such as conversion work, cold email, or an SEO audit.
The count changes often. The title says 47, but as I write this the repo lists 48 skills. I ran two of them across three sessions on a fake but realistic invoicing product, and each installed in about three seconds.
How it works
One idea explains everything. A skill named product-marketing writes one file, .agents/product-marketing.md, that records your product, audience, and positioning. Every other skill reads it first, so the advice comes from your business, not a generic template.
Each skill stays out of context until your request matches its description. It uses the open Agent Skills format that Anthropic released. Because every skill still reads the same context file, adding more skills doesn't add more setup. You fill one file, and all of them get sharper.
How you would use it
You install with npx skills, then ask in plain language or call a skill by name.
npx skills add coreyhaines31/marketingskills --skill cro product-marketing
/cro
Here is my landing page. Give me CRO feedback.
My first run had no context file, so the skill did careful but limited work. It flagged the vague headline and the missing security signal on a money product, yet it never reached the deeper problems, because it had no context file to work from.
Then I ran product-marketing, which read my README and drafted the context file in one pass. I ran the conversion skill again with the file in place. Same page, same skill, but a different diagnosis, because its top priority moved from "tighten the copy" to "you are talking to the wrong audience."
The file named my audience as solo freelancers, so the skill rewrote the headline from "the best invoicing solution for modern teams" to "invoicing for freelancers who bill by the hour."
The skills are sharp when the context file is good, and generic when it's empty. That's the whole product in one moment.
Where it fits
A few cases make it genuinely useful. A solo founder rewriting a landing page gets a senior audit in minutes. A small team planning a launch gets a shared framework. A freelancer on client CRO work gets a fast first draft.
The limits are built into how the skills work, so better prompts won't remove them. Know them before you decide.
- The advice is only as specific as the context file, so skip that step and it stays generic.
- Too many skills overlap. Six of them match "landing page" alone, for example, so the agent sometimes picks the wrong one.
- It advises but doesn't act. A skill writes recommendations and never touches your ad account, so connecting real tools is separate work.
- It also sells something. The free repo links to Magister, Corey's paid agent that runs these skills for you.
Verdict
With those limits clear, the verdict is simple. It's a strong helper for a marketer, not a replacement, and worth spending an afternoon on if you fill the context file. If you try it, keep four things in mind.
- Run product-marketing first, since every other skill reads what it writes.
- Install two or three skills for the task rather than all 48.
- Treat the output as a senior first draft, not a finished deliverable.
- Skip it if you expect it to run your marketing for you, or if you don't work in a terminal.