🤔 Don't know what an MCP is? Read this 30-second explainer

Model Context Protocol (MCP) is the open standard that lets AI assistants like Claude, Cursor, or Codex call external tools. Think of it as "USB for AI assistants" — you plug a tool in, the AI can use it. librecrawl-technical-seo-audit-mcp is one of those tools. Once installed, you just ask your AI assistant to audit a site, and it does. No GUI. No dashboard. No exports.

New to all this?

• Don't have Claude Code yet? → Install Claude Code (free for individuals).
• Prefer Cursor? → Get Cursor.
• Already have one of those? → Skip to Install in 60s.

🪄 The whole pitch in 4 lines

You:    Audit https://acme.com — full site, no caps, give me the zip
Agent:  → librecrawl_start_chunked_audit · polls until done · saves zip locally
You:    Show me broken pages + broken external links + hreflang errors
Agent:  → reads CSVs, prints filtered tables. Server already forgot the audit.

That's the product. Your AI assistant runs a full technical SEO audit for you. You get a branded PDF + 7 CSVs covering 50+ technical checks, ready to hand a client. The server wipes everything the moment you download.

🔥 Why this exists

There are great desktop SEO crawlers (you know the ones). There are great cloud SEO suites. There was no AI-native crawler. librecrawl-technical-seo-audit-mcp fills that gap with five things no comparable open-source MCP server does:

⚡ It runs inside your AI assistant

37 MCP tools your agent calls directly. No GUI app to babysit, no SaaS dashboard to log into, no CSV exports to upload to ChatGPT. You just ask.

🚀 Chunked-progressive crawler that never times out

Most SEO MCP servers (SiteAudit MCP, AgentAEO, SE Ranking MCP) run synchronously and disconnect on sites over a few hundred pages. librecrawl-technical-seo-audit-mcp runs the crawl in a background worker thread, persists progress to SQLite WAL, and returns a session_id in under 2 seconds. Your agent polls a tiny status tool until done. 10,000-page enterprise sites work the same as 50-page blogs. Survives PM2 / MCP-client restarts mid-crawl.

🛡️ Catches WAF challenges other crawlers silently misreport

Cloudflare, Akamai, DataDome, Imperva, and PerimeterX challenge pages are served as 200 OK but contain a JavaScript challenge instead of your content. Most crawlers report these as "page OK, all good". librecrawl-technical-seo-audit-mcp fingerprints the challenge in the response body and flags bot_block_challenge_detected. You see what's actually broken.

🤖 An AIMD controller tunes crawl delay live

Additive-Increase / Multiplicative-Decrease — the same algorithm TCP congestion control uses. Error rate > 10% → halve chunk, double delay. p95 latency > 1.5× target → 1.5× delay. Clean signals → additive decrease. Polite by construction. No rate-limit blow-ups. No manual tuning. Respects robots.txt Crawl-Delay floor.

🧹 Ephemeral by design — the agency-safe default

Once you download the zip, the server deletes the session row, every artifact file on disk, AND the upstream LibreCrawl crawl record. Per-audit server footprint after cleanup: 0 bytes, 0 rows. Auditing 50 client sites? Zero data persists where another operator could see it.

📄 Branded PDF reports ready to hand a client

WeasyPrint, A4, page numbers, footer on every page. Open in any PDF viewer. No SaaS watermark. Hand it to a client as your work.

⚡ Install in 60 seconds

curl -fsSL https://raw.githubusercontent.com/adityaarsharma/librecrawl-technical-seo-audit-mcp/main/install.sh | bash

The installer asks 3 questions (target client, optional Google PageSpeed API key, optional GSC integration) and writes a ready-to-use MCP entry into your Claude / Cursor / Codex / Windsurf config. Done.

git clone https://github.com/adityaarsharma/librecrawl-technical-seo-audit-mcp.git
cd librecrawl-technical-seo-audit-mcp
python3 -m venv venv && source venv/bin/activate
pip install httpx mcp weasyprint markdown fpdf2
# Start LibreCrawl backend on :5080 (see install.sh for Docker compose)
python server.py

{
  "mcpServers": {
    "librecrawl": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "http://127.0.0.1:5081/mcp"]
    }
  }
}

🚀 50+ checks every audit

🔗 Every outbound URL HEAD/GET-validated into 17 status classes — ok · redirect · forbidden · not_found · timeout · dns_error · ssl_error · connection_refused · etc. Per-target: final URL after redirects, source pages, anchor text, response time, server header.

📈 GSC merge — pull Google Search Console data, call librecrawl_merge_gsc_data(crawl_id, gsc_data). URLs normalised before joining. Emits 4 extra CSVs: per-page-with-gsc · gsc-winners · gsc-losers (high impr + CTR <2%) · gsc-quick-wins (position 11–20 + impr ≥100).

🆚 Feature comparison to other on-site SEO crawlers

This is a factual feature comparison. Prices were checked at publication and may have changed — see each vendor's site for current pricing. Brand names belong to their respective owners.

Reading guide: if you currently use a paid on-site crawler and your workflow is "crawl → export CSVs → analyse", librecrawl-technical-seo-audit-mcp covers that flow inside your AI assistant for £0 with no page caps. If your workflow depends on JavaScript-rendered SPAs, that's on the roadmap but not shipped yet — use the desktop tool for now.

📊 What every audit produces

Single zip, 8 files:

📖 Your first audit

You:   Audit https://example.com — full site, no caps

Agent: → librecrawl_start_chunked_audit(url=..., total_max_pages=10000)
         returns session_id in <2s

       → polls librecrawl_audit_status every 25s
         status: crawling, pages_done: 47,  current_delay_ms: 250
         status: crawling, pages_done: 312, last chunk p95: 480ms, err_rate: 0%
         status: done,     pages_done: 534, artifacts_ready: true

       → librecrawl_audit_zip(session_id, auto_cleanup=True)
         returns base64 zip (8 files, 320 KB)
         SAVES LOCALLY as example.com-1780572742.zip
         Server wiped: session_rows=4, files=8, upstream_crawl=1

You:   Show me broken pages + broken external links

Agent: → unzips, reads per-page.csv (filters status_4xx OR status_5xx)
       → reads external-links.csv (filters not_found · forbidden · 5xx · timeout)
       → prints both tables

Local zip is the only copy. Server is back to zero state.

🛣️ Roadmap

Not planned: keyword research, backlink analysis, SERP tracking. Those are different problems with different MCP servers (DataForSEO, etc.). This tool is laser-focused on technical on-site SEO crawling.

Open an issue to bump priorities or request a check.

🏗️ Architecture

┌─────────────────────────────────────────────────────────────┐
│  MCP client (Claude Code / Desktop / Cursor / Codex …)      │
└────────────────────────────┬────────────────────────────────┘
                             │  streamable HTTP or stdio
                             ▼
┌─────────────────────────────────────────────────────────────┐
│  librecrawl-technical-seo-audit-mcp wrapper  (server.py — FastMCP, 37 tools)    │
│  ┌─────────────────┐    ┌──────────────────────────────┐    │
│  │ runner.py       │    │ external_links / schema /    │    │
│  │ background      │    │ content_audit / extended_    │    │
│  │ worker thread   │    │ checks / sitemap_fill /      │    │
│  │ AIMD controller │    │ pdf_report                   │    │
│  └────────┬────────┘    └──────────────────────────────┘    │
│           │                                                  │
│  ┌────────▼────────┐    ┌──────────────────────────────┐    │
│  │ state.py        │    │ libreclient.py — typed       │    │
│  │ SQLite WAL      │    │ wrapper to upstream API      │    │
│  │ session state   │    └──────────────┬───────────────┘    │
│  └─────────────────┘                   │                    │
└─────────────────────────────────────────┼────────────────────┘
                                          │
                                          ▼
                          ┌──────────────────────────────┐
                          │  LibreCrawl Flask backend    │
                          │  :5080 — single-tenant       │
                          │  crawls + extracts SEO data  │
                          └──────────────────────────────┘

⚙️ Configuration

🛠️ 37 MCP tools

📜 License & trademarks

Code: MIT. Use it on client work, agency work, internal tools, anything. No attribution required (but appreciated). See LICENSE.

Trademarks. All third-party product names mentioned in this README (including any names referenced in the comparison table) are property of their respective owners. This project is not affiliated with, endorsed by, or sponsored by any third-party tool vendor. Comparisons are based on publicly available information at the time of writing and exist for the purpose of informing readers evaluating different categories of SEO tooling.

🙏 Credits

• LibreCrawl — the upstream open-source crawler this MCP server wraps. MIT. Please go star them — this project would not exist without that work.
• Anthropic Model Context Protocol — the protocol this server speaks
• WeasyPrint — Markdown → HTML → PDF rendering
• FastMCP — the Python MCP server framework