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André Ahlert
André Ahlert

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I built an MCP Server that lets Claude manage your Substack

#automation #cli #mcp #showdev

The Substack web UI is fine for casual use, but if you're a power user who publishes daily, manages engagement, and wants to automate interactions, you need something faster.

TUI Gif Interface Demo

I built @postcli/substack, a tool that gives you three interfaces to Substack:

1. CLI - Direct commands from your terminal

postcli-substack notes publish "Shipping fast from the terminal"
postcli-substack posts list --limit 5
postcli-substack feed --tab for-you
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2. TUI - Full interactive terminal UI with 6 tabs

postcli-substack tui
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Navigate with j/k or arrow keys, scroll with mouse wheel, open posts in browser with 'o'. It's keyboard-driven and fast.

3. MCP Server - 16 tools for AI agents

{
  "mcpServers": {
    "substack": {
      "command": "postcli-substack",
      "args": ["mcp"]
    }
  }
}
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Tell Claude "like back everyone who liked my last note" and it just works.

The automation engine

The part I'm most proud of is the automation engine. It uses SQLite to track processed entities (no duplicate actions) and supports triggers like:

  • Someone likes your note → auto-like their latest note back
  • New note from specific authors → auto-like or restack
  • New post from specific publications → auto-restack

Auth without API keys

Substack doesn't have a public API. Auth works by extracting your existing Chrome session cookies (AES-128-CBC decryption) or manual cookie entry.

postcli-substack auth login
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Install 

npm install -g @postcli/substack
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89 tests. CI on Node 18/20/22. Open source (AGPL-3.0).

GitHub: https://github.com/postcli/substack
NPM: https://www.npmjs.com/package/@postcli/substack

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