Marketing Skills adds a skill that reverse-engineers how a company grew

Corey Haines added /reverse-engineer-marketing to Marketing Skills, his open-source library of marketing skills for coding agents. Give it a company's domain and it works out how that company grew from public evidence.

The skill builds one monthly curve of the company's traffic and brand searches, then logs every dated move it can find against that curve, such as pricing changes, new page families, the first month an ad pixel appeared, homepage headline changes, launches and job posts. Free collectors read the sitemap, web archives, DNS records, certificate logs, public job boards and App Store reviews. Moves that land within six weeks of each other are grouped, and the skill compares growth in the three months after each group with the three months before. It treats timing as a lead, not proof.

It then puts the findings next to your own data and competitors, looks for where the company is weak in low-star reviews and switching posts, and ends with plays. Each play names the skill in the library that runs it and comes with a prompt you can paste.

There are six modes. Teardown is the default and runs every stage. Content looks only at what works on a company's channels, Quick is a first look on a small budget, and Funnel Hack maps the whole funnel. Landscape compares three to five competitors and writes a CSV matrix, and Watch reruns a finished teardown each month and reports only new moves.

Signing up, booking a demo or buying from the company happens only with your approval for each action, under your real name. The skill runs a bundled Node script from your project and fetches public pages, so read it before you install it. Keyword and traffic estimates need a paid data source such as DataForSEO, Semrush, Ahrefs or Similarweb, with a default cap of $5 on paid calls.

Marketing Skills is free and MIT-licensed, with 53 skills. npx skills add coreyhaines31/marketingskills installs it for Claude Code, Codex, Cursor and other agents that read skills.