How do I get my Substack API token?

Log in to your Substack publication at **yourdomain.substack.com**. Navigate to **Settings** from the left sidebar. Look for the **Publication API** or **Developer** section. Generate an API token and copy it. Paste it into the configuration field below. Note: Substack's API is currently in limited availability — check Substack's developer page for the latest access information.

Can I draft and schedule newsletter posts?

Yes. Your AI agent can create draft posts with title, body content, subtitle, and metadata. You can then schedule them for a specific date and time — managing your entire editorial calendar conversationally.

Can I track how many subscribers I gained this month?

Yes. Ask your AI agent for subscriber growth metrics and get total subscribers, new subscribers this month, churn rate, and free vs. paid subscriber breakdown.

Does this work with paid Substack publications?

Yes. The integration supports both free and paid publications. You can manage paywalled content, check paid subscriber counts, and analyze revenue metrics through your AI agent.

Substack MCP Server for LangChain 6 tools — connect in under 2 minutes

Name: Substack
Availability: InStock
Author: Vinkius

python.langchain.com/docs/integrations/tools/mcp

Built by Vinkius GDPR 6 Tools Framework

LangChain is the leading Python framework for composable LLM applications. Connect Substack through Vinkius and LangChain agents can call every tool natively. combine them with retrievers, memory, and output parsers for sophisticated AI pipelines.

Get MCP Server for AI Agents

ASK AI ABOUT THIS MCP SERVER

Open in ChatGPT Open in Claude Open in Perplexity

Vinkius supports streamable HTTP and SSE.

python

import asyncio
from langchain_mcp_adapters.client import MultiServerMCPClient
from langchain_openai import ChatOpenAI
from langgraph.prebuilt import create_react_agent

async def main():
    # Your Vinkius token. get it at cloud.vinkius.com
    async with MultiServerMCPClient({
        "substack": {
            "transport": "streamable_http",
            "url": "https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp",
        }
    }) as client:
        tools = client.get_tools()
        agent = create_react_agent(
            ChatOpenAI(model="gpt-4o"),
            tools,
        )
        response = await agent.ainvoke({
            "messages": [{
                "role": "user",
                "content": "Using Substack, show me what tools are available.",
            }]
        })
        print(response["messages"][-1].content)

asyncio.run(main())

Fully ManagedVinkius Servers

60%Token savings

High SecurityEnterprise-grade

IAMAccess control

EU AI ActCompliant

DLPData protection

V8 IsolateSandboxed

Ed25519Audit chain

<40msKill switch

Stream every event to Splunk, Datadog, or your own webhook in real-time

* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure

About Substack MCP Server

Connect Substack to your AI agent and manage your newsletter publication conversationally.

LangChain's ecosystem of 500+ components combines seamlessly with Substack through native MCP adapters. Connect 6 tools via Vinkius and use ReAct agents, Plan-and-Execute strategies, or custom agent architectures. with LangSmith tracing giving full visibility into every tool call, latency, and token cost.

What you can do

Post Management — List, create, and manage newsletter posts including drafts, published, and scheduled content.
Subscriber Insights — Query subscriber counts, growth trends, and audience demographics.
Publication Settings — Access and modify publication metadata, categories, and custom domains.
Content Analytics — Track open rates, click rates, and engagement metrics per post.

The Substack MCP Server exposes 6 tools through the Vinkius. Connect it to LangChain in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.

How to Connect Substack to LangChain via MCP

Follow these steps to integrate the Substack MCP Server with LangChain.

Install dependencies

Run pip install langchain langchain-mcp-adapters langgraph langchain-openai

Replace the token

Replace [YOUR_TOKEN_HERE] with your Vinkius token

Run the agent

Save the code and run python agent.py

Explore tools

The agent discovers 6 tools from Substack via MCP

Why Use LangChain with the Substack MCP Server

LangChain provides unique advantages when paired with Substack through the Model Context Protocol.

The largest ecosystem of integrations, chains, and agents. combine Substack MCP tools with 500+ LangChain components

Agent architecture supports ReAct, Plan-and-Execute, and custom strategies with full MCP tool access at every step

LangSmith tracing gives you complete visibility into tool calls, latencies, and token usage for production debugging

Memory and conversation persistence let agents maintain context across Substack queries for multi-turn workflows

Substack + LangChain Use Cases

Practical scenarios where LangChain combined with the Substack MCP Server delivers measurable value.

RAG with live data: combine Substack tool results with vector store retrievals for answers grounded in both real-time and historical data

Autonomous research agents: LangChain agents query Substack, synthesize findings, and generate comprehensive research reports

Multi-tool orchestration: chain Substack tools with web scrapers, databases, and calculators in a single agent run

Production monitoring: use LangSmith to trace every Substack tool call, measure latency, and optimize your agent's performance

Substack MCP Tools for LangChain (6)

These 6 tools become available when you connect Substack to LangChain via MCP:

get_leaderboard

Get leaderboard

get_post

Get post

get_post_stats

Get post stats

get_publication_info

Get publication info

list_posts

List recent posts

list_subscribers

List subscribers

Example Prompts for Substack in LangChain

Ready-to-use prompts you can give your LangChain agent to start working with Substack immediately.

"How many subscribers does my Substack have?"

"Draft a new newsletter post titled 'The Future of AI in Sales'."

"What was the open rate on my last newsletter?"

Troubleshooting Substack MCP Server with LangChain

Common issues when connecting Substack to LangChain through the Vinkius, and how to resolve them.

MultiServerMCPClient not found

Install: pip install langchain-mcp-adapters

Substack + LangChain FAQ

Common questions about integrating Substack MCP Server with LangChain.

How does LangChain connect to MCP servers?

Use langchain-mcp-adapters to create an MCP client. LangChain discovers all tools and wraps them as native LangChain tools compatible with any agent type.

Which LangChain agent types work with MCP?

All agent types including ReAct, OpenAI Functions, and custom agents work with MCP tools. The tools appear as standard LangChain tools after the adapter wraps them.