MCP Cloudflare CrunchTools

A secure MCP (Model Context Protocol) server for Cloudflare DNS, Transform Rules, Page Rules, and cache management.

Overview

This MCP server is designed to be:

• Secure by default - Threat modeling, input validation, and token protection
• No third-party services - Runs locally via stdio, your API token never leaves your machine
• Cross-platform - Works on Linux, macOS, and Windows
• Automatically updated - GitHub Actions monitor for CVEs and update dependencies
• Containerized - Available at quay.io/crunchtools/mcp-cloudflare built on Hummingbird Python base image

Naming Convention

Component	Name
GitHub repo	crunchtools/mcp-cloudflare
Container	quay.io/crunchtools/mcp-cloudflare
Python package (PyPI)	mcp-cloudflare-crunchtools
CLI command	mcp-cloudflare-crunchtools
Module import	mcp_cloudflare_crunchtools

Why Hummingbird?

The container image is built on the Hummingbird Python base image from Project Hummingbird, which provides:

• Minimal CVE exposure - Hummingbird images are built with a minimal package set, dramatically reducing the attack surface compared to general-purpose images
• Regular updates - Security patches are applied promptly, keeping CVE counts low
• Optimized for Python - Pre-configured Python environment with uv package manager for fast, reproducible builds
• Production-ready - Designed for production workloads with proper signal handling and non-root user defaults

This means your MCP server runs in a hardened environment with fewer vulnerabilities than typical Python container images

Features

Zone Management (2 tools)

• list_zones - List all zones accessible by your API token
• get_zone - Get zone details by ID or domain name

DNS Records (5 tools)

• list_dns_records - List DNS records with filtering
• get_dns_record - Get a single DNS record
• create_dns_record - Create A, AAAA, CNAME, MX, TXT, NS, SRV, CAA records
• update_dns_record - Update existing records
• delete_dns_record - Delete records

Transform Rules (6 tools)

• list_request_header_rules / set_request_header_rules - Modify request headers
• list_response_header_rules / set_response_header_rules - Modify response headers
• list_url_rewrite_rules / set_url_rewrite_rules - URL path/query rewrites

Page Rules (4 tools)

• list_page_rules - List all page rules
• create_page_rule - Create redirects, cache settings, SSL modes
• update_page_rule - Modify existing rules
• delete_page_rule - Remove rules

Cache Management (1 tool)

• purge_cache - Purge by URL, tag, host, prefix, or everything

Installation

With uvx (Recommended)

uvx mcp-cloudflare-crunchtools

With pip

pip install mcp-cloudflare-crunchtools

With Container

podman run -e CLOUDFLARE_API_TOKEN=your_token \
    quay.io/crunchtools/mcp-cloudflare

Configuration

Creating a Cloudflare API Token

1. Navigate to API Tokens

   • Go to https://dash.cloudflare.com/profile/api-tokens
   • Click "Create Token"
   • Click "Get started" next to "Create Custom Token"

2. Configure Token Name

   • Enter: mcp-cloudflare-crunchtools

3. Configure Permissions

   The Permissions section has three dropdowns per row:

   • First dropdown: Resource type (Account or Zone)
   • Second dropdown: Specific permission category
   • Third dropdown: Access level (Read or Edit)

   Click "+ Add more" to add each permission row. For full management, add:

   Resource	Permission	Access
   Zone	Zone	Read
   Zone	DNS	Edit
   Zone	Page Rules	Edit
   Zone	Transform Rules	Edit
   Zone	Cache Purge	Purge

4. Configure Zone Resources

   • First dropdown: Select "Include"
   • Second dropdown: Select "All zones" or "Specific zone"

5. Configure Client IP Address Filtering (Optional)

   • Click "Use my IP" button to restrict token to your current IP

6. Create and Copy Token

   • Click "Continue to summary" → "Create Token"
   • IMPORTANT: Copy the token immediately - it's only shown once!

Add to Claude Code

claude mcp add mcp-cloudflare-crunchtools \
    --env CLOUDFLARE_API_TOKEN=your_token_here \
    -- uvx mcp-cloudflare-crunchtools

Or for the container version:

claude mcp add mcp-cloudflare-crunchtools \
    --env CLOUDFLARE_API_TOKEN=your_token_here \
    -- podman run -i --rm -e CLOUDFLARE_API_TOKEN quay.io/crunchtools/mcp-cloudflare

Permission Sets by Use Case

Read-Only (viewing only)

Resource	Permission	Access
Zone	Zone	Read
Zone	DNS	Read

DNS Management Only

Resource	Permission	Access
Zone	Zone	Read
Zone	DNS	Edit

Full Management (all features)

Resource	Permission	Access
Zone	Zone	Read
Zone	DNS	Edit
Zone	Page Rules	Edit
Zone	Transform Rules	Edit
Zone	Cache Purge	Purge

Usage Examples

List Your Zones

User: List my Cloudflare zones
Assistant: [calls list_zones]

Create a DNS Record

User: Create an A record for www.example.com pointing to 192.168.1.1
Assistant: [calls create_dns_record with type=A, name=www, content=192.168.1.1]

Add Security Headers

User: Add X-Content-Type-Options: nosniff to all responses for zone abc123...
Assistant: [calls set_response_header_rules with appropriate rule]

Purge Cache

User: Purge the cache for https://example.com/styles.css
Assistant: [calls purge_cache with files=["https://example.com/styles.css"]]

Security

This server was designed with security as a primary concern. See SECURITY.md for:

• Threat model and attack vectors
• Defense in depth architecture
• Token handling best practices
• Input validation rules
• Audit logging

Key Security Features

1. Token Protection

   • Stored as SecretStr (never accidentally logged)
   • Environment variable only (never in files or args)
   • Sanitized from all error messages

2. Input Validation

   • Pydantic models for all inputs
   • Allowlist for record types, actions
   • Strict format validation for IDs

3. API Hardening

   • Hardcoded API base URL (prevents SSRF)
   • TLS certificate validation
   • Request timeouts
   • Response size limits

4. Automated CVE Scanning

   • GitHub Actions scan dependencies weekly
   • Automatic PRs for security updates
   • Dependabot alerts enabled

Development

Setup

git clone https://github.com/crunchtools/mcp-cloudflare.git
cd mcp-cloudflare
uv sync

Run Tests

uv run pytest

Lint and Type Check

uv run ruff check src tests
uv run mypy src

Build Container

podman build -t mcp-cloudflare .

License

AGPL-3.0-or-later

Contributing

Contributions welcome! Please read SECURITY.md before submitting security-related changes.

Links

• Cloudflare API Documentation
• FastMCP Documentation
• MCP Specification
• crunchtools.com