Substack Publisher MCP Server

MCP server for Substack's official Publisher API

Local serverstdio

What is the Substack Publisher MCP MCP server?

MCP server for Substack's official Publisher API. Exposed over MCP by the substack publisher mcp mcp server, that capability becomes something an assistant can invoke while it works, not something you go and do afterwards.

What it actually does

The first MCP server for Substack's official Publisher API. Query post analytics, subscriber counts, and publication data directly from Claude, Cursor, or any MCP client.

Its toolset

Everything the assistant can do here goes through one of these:

  • list_publications — List configured publications
  • list_posts — List published posts
  • get_post — Get a specific post by URL slug
  • get_post_stats — Get engagement stats for a post
  • get_subscriber_counts — Get daily subscriber counts by type
  • get_subscriber — Look up a subscriber by email

Configuration

You will need 4 environment variables: SUBSTACK_API_KEY, SUBSTACK_API_KEY_MAIN, SUBSTACK_API_KEY_TECH, SUBSTACK_API_KEY_COMPANY. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

  • Node.js 18+. Check with node --version; install from nodejs.org if missing. - Substack Publisher API key. Generate one from your publication's Substack dashboard. If you don't see a Publisher API option there, it may not be enabled for your publication yet; see the Publisher API docs for availability.

Adding it to your client

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client. The configuration blocks on this page cover the common clients.

When to reach for it

Among the team communication options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. Substack Publisher MCP's toolset — list_publications, list_posts, get_post and 3 more — is a fair guide to whether it matches your workflow. It is maintained by dkships; worth a glance at recent repository activity before you build anything load-bearing on it.

This entry was verified against Substack Publisher MCP's own documentation before publication; SyncDev keeps the directory reviewed rather than auto-generated.

Caveats

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • MCP clients confirm each tool call by default. Leave that on until you have watched what the substack publisher mcp mcp server does with a few real requests.

Available tools

ToolWhat it does
list_publicationsList configured publications
list_postsList published posts
get_postGet a specific post by URL slug
get_post_statsGet engagement stats for a post
get_subscriber_countsGet daily subscriber counts by type
get_subscriberLook up a subscriber by email

How to install the Substack Publisher MCP MCP server

{
  "mcpServers": {
    "substack": {
      "command": "node",
      "args": ["/path/to/substack-publisher-mcp/dist/index.js"],
      "env": {
        "SUBSTACK_API_KEY_MAIN": "your-main-blog-key",
        "SUBSTACK_API_KEY_TECH": "your-tech-newsletter-key",
        "SUBSTACK_API_KEY_COMPANY": "your-company-updates-key"
      }
    }
  }
}

Configuration as documented by the project. Restart the client after saving.

Configuration

  • Node.js 18+. Check with node --version; install from nodejs.org if missing. - Substack Publisher API key. Generate one from your publication's Substack dashboard. If you don't see a Publisher API option there, it may not be enabled for your publication yet; see the Publisher API docs for availability.
VariableDescriptionRequired
SUBSTACK_API_KEYCredential the server authenticates with.Yes
SUBSTACK_API_KEY_MAINCredential the server authenticates with.Yes
SUBSTACK_API_KEY_TECHCredential the server authenticates with.Yes
SUBSTACK_API_KEY_COMPANYCredential the server authenticates with.Yes

Example prompts to try

  • Use Substack Publisher MCP to list publications.
  • Use Substack Publisher MCP to list posts.
  • Use Substack Publisher MCP to get post.

Frequently asked questions

It connects Substack Publisher MCP to MCP-compatible AI assistants such as Claude and Cursor, exposing 6 tools (list_publications, list_posts, get_post, and more) that the assistant can call on your behalf. Instead of copying data back and forth by hand, the assistant works with Substack Publisher MCP directly.