Substack MCP Server

A Model Context Protocol (MCP) server for scraping and analyzing Substack newsletters. Enables LLMs to fetch posts from any public Substack publication.

Features

• Get Posts: Fetch recent or top posts from any Substack
• Get Post Content: Retrieve full text of individual posts
• Search Posts: Search within a newsletter
• Batch Fetch: Scrape multiple newsletters at once
• Newsletter Info: Get author and recommendation data

Installation

pip install -r requirements.txt

Or manually:

pip install mcp substack-api pydantic httpx

Usage

Running the Server

python server.py

MCP Client Configuration

For Claude Desktop or similar MCP clients, add to your config:

{
  "mcpServers": {
    "substack": {
      "command": "python",
      "args": ["/path/to/server.py"]
    }
  }
}

Tools

substack_get_posts

Fetch posts from a newsletter.

{
  "publication_url": "lenny",  # or "https://lenny.substack.com"
  "limit": 20,
  "sorting": "top",  # or "new"
  "response_format": "markdown"  # or "json"
}

substack_get_post_content

Get full content of a specific post (free posts only).

{
  "post_url": "https://example.substack.com/p/post-slug",
  "response_format": "markdown"
}

substack_search_posts

Search posts within a newsletter.

{
  "publication_url": "stratechery",
  "query": "AI",
  "limit": 10
}

substack_batch_get_posts

Fetch from multiple newsletters at once.

{
  "publication_urls": ["lenny", "stratechery", "platformer"],
  "posts_per_publication": 5,
  "sorting": "top"
}

substack_get_newsletter_info

Get newsletter metadata and recommendations.

{
  "publication_url": "lenny"
}

Limitations

• Paywalled content: Cannot access subscriber-only posts without authentication
• Rate limiting: Substack may rate-limit requests; includes 0.5s delays for batch operations
• Unofficial API: Uses reverse-engineered API that may change
• Network restrictions: Some environments (corporate proxies, certain cloud platforms) may block Substack API requests

Credits

Built on substack-api Python library.