free-seo-mcp: free keyword research MCP server

Keyword research for Claude, Cursor and any MCP client, with a $0 budget. You get search suggestions, Google Trends, real Bing search volume, Reddit threads and competitor sitemaps in one server. No Ahrefs, Semrush or DataForSEO subscription.

Русская версия

What you can ask your agent

Expand "running shoes" in English and Spanish, estimate volumes against "trail running shoes", split them into high/mid/low and save to project shoes.

Pull every URL from the competitor's sitemap and outline their top 10 pages.

Find Reddit threads where people complain about running shoes and list their exact words.

Why it exists

Google shows exact search volume only to advertisers who spend money. Paid SEO tools resell estimates of that number. free-seo-mcp builds its own estimate from free sources:

| Source | What you get | |---|---| | Google, YouTube, Bing, DuckDuckGo autocomplete | Phrases people type, scored by position and repeat count | | Google Trends | Relative demand, rising queries, demand by country | | Bing Webmaster API | Real weekly impressions (free API key) | | Reddit | Buyer language, questions, objections | | Competitor sites | Sitemap URLs, title, description, h1 to h3 |

estimate_volumes compares each keyword with one anchor in Google Trends. It gives the anchor an absolute number: your own figure, or Bing impressions times a multiplier. Each keyword comes back with an estimated monthly volume, a high/mid/low tier, a confidence level and the method used.

Tools

| Tool | Purpose | |---|---| | suggest | Autocomplete from one engine, with positions | | expand_alphabet | Seed plus each letter of the alphabet, scored | | expand_questions | Question prefixes per language (how, why, what is...) | | expand_multilingual | One seed across several hl:gl locales | | trends_compare | Up to 5 keywords on one 0 to 100 scale | | trends_related | Top and rising related queries | | trends_by_region | Demand by country or region | | bing_keyword | Bing impressions for a period | | bing_related_keywords | Related keywords with impressions | | bing_keyword_history | Weekly impression series | | estimate_volumes | Volume estimate and tier for a keyword list | | reddit_search | Threads with score, comment count and snippet | | sitemap_urls | Every URL from a site's sitemaps | | page_outline | Title, meta description, headings, word count | | keywords_save, keywords_load | CSV keyword store per project and language |

The keyword_research_workflow prompt walks the agent through seeds, expansion, estimates, clusters and saving.

Languages with built-in alphabets and question prefixes: English, Russian, Spanish, Portuguese, German, French, Italian. Any other hl:gl pair works for autocomplete and Trends.

Quick start

Install uv, then:

git clone https://github.com/JohnWayneeee/free-seo-mcp.git
cd free-seo-mcp
uv sync

Claude Code

claude mcp add free-seo -- uv run --directory /path/to/free-seo-mcp free-seo-mcp

Claude Desktop, Cursor, Windsurf

{
  "mcpServers": {
    "free-seo": {
      "command": "uv",
      "args": ["run", "--directory", "/path/to/free-seo-mcp", "free-seo-mcp"],
      "env": { "FREE_SEO_DATA_DIR": "/path/to/seo-data" }
    }
  }
}

Configuration

| Variable | Default | Meaning | |---|---|---| | FREE_SEO_BING_API_KEY | none | Turns on Bing tools and Bing-based estimates | | FREE_SEO_DATA_DIR | ./seo-data | Keyword CSVs and cache | | FREE_SEO_MIN_DELAY | 0.4 | Seconds between requests to one host | | FREE_SEO_PROXY | none | HTTP(S) proxy for every request | | FREE_SEO_CACHE_TTL_DAYS | 7 | Cache lifetime |

Get a Bing key: sign in to Bing Webmaster Tools, add and verify your site, open Settings, then API access, and generate a key.

Limits

• Trust the tiers more than the exact numbers.
• Google Trends rounds rare keywords to 0. The server reports them as "below 1% of the anchor".
• Autocomplete, Trends and Reddit use unofficial endpoints with rate limits. The server waits between requests, backs off on HTTP 429 and caches results on disk. It does not solve CAPTCHAs.
• Reddit returns 403 to some networks. Set FREE_SEO_PROXY if you hit it.

Development

uv run ruff check && uv run ruff format --check
uv run pytest -q          # offline, mocked
uv run pytest -m live     # real endpoints

Pull requests welcome. New autocomplete engines and language packs are the easiest place to start.

License

MIT

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