Marketing & Business · Blog Post

Claude SEO: a universal, falsifiable SEO audit plugin for Claude Code

Most "SEO skills" boil down to a checklist prompt. This one runs 25 sub-skills through up to 18 parallel specialist agents and hands back a prioritized action plan where every recommendation carries observable evidence and a measurable way to confirm it worked — not just an opinion about your title tags.

By Mehadi Hasan 8 min read

What it is

claude-seo is an open-source SEO analysis plugin for Claude Code that runs a full site audit as a coordinated agent swarm rather than a single long prompt. It has passed 12,000 GitHub stars with commits landing daily, and the whole thing is MIT-licensed and keyless by default — no paid API required to get a real audit out of it.

The differentiator the README leads with is falsifiability: a finding isn't "improve your meta descriptions," it's the specific pages missing them, the crawl evidence that surfaced it, and the leading indicator to check afterward to confirm the fix actually moved something.

Coverage across 7 domains

12.4k+ GitHub stars
25 Sub-skills
18 Parallel specialist agents
32 User commands

Technical SEO

Crawl analysis, Core Web Vitals (LCP, INP, CLS), indexation signals

Content Quality (E-E-A-T)

Expertise, authoritativeness, and trustworthiness scoring per Search Quality Rater Guidelines

Schema.org Markup

Detection, validation, and generation across 10+ active types, plus deprecated-type flagging

AI Search (GEO)

Passage citability, question-based content hierarchy, entity presence, AI-citability gaps

Backlinks & Authority

Link-profile analysis via Moz, Bing, and Common Crawl

Local SEO

Google Business Profile audits, NAP consistency, review sentiment

E-commerce & International

Product schema validation, hreflang i18n audits, multi-location doorway-page prevention

Optional integrations, not requirements

The core plugin works from crawl data and free sources with zero paid services. If you already pay for these, pluggable MCP extensions add live data on top: DataForSEO (SERP, keywords, backlinks, AI visibility), Firecrawl (full-site crawling), Ahrefs (official backlink/organic keyword data), SE Ranking (AI share-of-voice across ChatGPT, Gemini, Perplexity), Profound (LLM citation tracking over time), Bing Webmaster (submission), and Unlighthouse (multi-page Lighthouse testing).

Installation

Fastest path, if you're on Claude Code 1.0.33 or later:

Claude Code plugin marketplace

/plugin marketplace add AgriciDaniel/claude-seo
/plugin install claude-seo@agricidaniel-claude-seo
/seo setup

Manual install works the same on any OS:

macOS / Linux

git clone --depth 1 https://github.com/AgriciDaniel/claude-seo.git
bash claude-seo/install.sh

Windows (PowerShell)

git clone --depth 1 https://github.com/AgriciDaniel/claude-seo.git
powershell -ExecutionPolicy Bypass -File claude-seo\install.ps1

Using it day to day

Run /seo setup once per project, then ask for what you need — a full audit, a schema-markup pass, a GEO/AI-citability check on a specific set of pages. The 18 specialist agents run in parallel where the task allows it, so a full-site audit doesn't mean waiting on 25 sub-skills sequentially.

The headless renderer (scripts/render_page.py, via Playwright) matters if your site is a JS-heavy SPA — without it, a crawl-based audit can miss content that only appears after client-side rendering.

My take

The falsifiability framing is the real contribution here — an SEO recommendation that comes with its own evidence and its own success metric is a fundamentally different artifact than a bullet list of "best practices," and it's what makes the output usable without re-deriving whether the agent is right.

If SEO is one slice of a broader marketing need, Marketing Skills covers more ground at shallower depth per topic; reach for this one specifically when SEO is the actual bottleneck, not a nice-to-have.

Frequently asked questions

Do I need paid SEO tools to use it?

No — the core plugin is keyless and MIT-licensed, working from crawl data and free sources. Optional MCP extensions (DataForSEO, Firecrawl, Ahrefs, SE Ranking, Profound, Bing Webmaster) add live SERP, backlink, and AI-citation data if you have those accounts.

What does "falsifiable" mean for a recommendation?

Every finding ships with observable evidence and a measurable leading indicator, not just an opinion — so "fix your title tags" comes with the actual crawl data showing which pages are missing them and what to check afterward to confirm it worked.

What is GEO/AEO, and why does an SEO skill cover it?

Generative/Answer Engine Optimization — making content citable by AI search surfaces like ChatGPT, Gemini, and AI Overviews, not just ranking in traditional blue-link results. The sub-skills score passage citability and entity presence specifically for that.

Is there a paid version?

The public AgriciDaniel/claude-seo repo is fully MIT with no membership required. A separate "Community" fork (AI-Marketing-Hub/claude-seo) offers early-access features for paying members, but it is not required for the core plugin.