# MCP LinkedIn Poster (TypeScript)
An **MCP (Model Context Protocol) server** that allows ChatGPT / Claude Desktop to **post content to LinkedIn** using the official **LinkedIn UGC Posts API** and an **OAuth 2.0 access token**.
This server runs locally and is designed to be registered in your **ChatGPT / Claude MCP server settings**.
---
## What this does
- Runs an MCP server over **stdio**
- Accepts post requests from ChatGPT / Claude
- Publishes text posts to **your LinkedIn profile**
- Uses **LinkedIn OAuth (3-legged)** authentication
- Reads secrets securely via environment variables
---
## Project structure
mcp-linkedin-poster/
├─ src/
│ └─ index.ts # main MCP server (TypeScript source)
├─ dist/
│ └─ index.js # compiled output (what Node actually runs)
├─ .env # environment variables (DO NOT COMMIT)
├─ package.json
├─ tsconfig.json
└─ README.md
yaml
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### What is `dist`?
`dist` stands for **distribution**.
It contains the compiled JavaScript output generated from TypeScript.
You **edit** `src/index.ts`
You **run** `dist/index.js`
---
## Install
```bash
npm install
Build
Compile TypeScript → JavaScript:
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npx tsc
This generates:
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dist/index.js
Run locally (sanity check)
bash
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node dist/index.js
If environment variables are missing you will see:
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Missing env LINKEDIN_ACCESS_TOKEN
Missing env LINKEDIN_AUTHOR_URN
That is expected until setup is complete.
Environment variables (.env)
Create a file named .env in the project root:
env
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LINKEDIN_ACCESS_TOKEN=
LINKEDIN_AUTHOR_URN=
LINKEDIN_VERSION=202502
What each variable is
Variable Description
LINKEDIN_ACCESS_TOKEN OAuth 2.0 member access token from LinkedIn
LINKEDIN_AUTHOR_URN Your LinkedIn profile URN (urn:li:person:...)
LINKEDIN_VERSION LinkedIn API version header (optional, safe to keep)
⚠️ Never commit .env
Add it to .gitignore.
How to get LINKEDIN_ACCESS_TOKEN
Go to https://www.linkedin.com/developers/
Open your LinkedIn app
Use OAuth 2.0 → Token Generator
Select scope:
w_member_social (required for posting)
Generate token
Copy it as a single line
Paste into .env:
env
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LINKEDIN_ACCESS_TOKEN=PASTE_TOKEN_HERE
How to get LINKEDIN_AUTHOR_URN
Method (recommended): LinkedIn userinfo endpoint
Curl
bash
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curl -X GET "https://api.linkedin.com/v2/userinfo" \
-H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
-H "Content-Type: application/json"
Example response:
json
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{
"sub": "8qD1tr1-1m",
"name": "Your Name"
}
Your author URN becomes:
env
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LINKEDIN_AUTHOR_URN=urn:li:person:8qD1tr1-1m
Windows PowerShell version
powershell
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$token="YOUR_ACCESS_TOKEN"
Invoke-RestMethod `
-Uri "https://api.linkedin.com/v2/userinfo" `
-Headers @{ Authorization = "Bearer $token" }
Example: LinkedIn post via curl (UGC API)
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curl -X POST "https://api.linkedin.com/v2/ugcPosts" \
-H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
-H "X-Restli-Protocol-Version: 2.0.0" \
-H "Content-Type: application/json" \
-d '{
"author": "urn:li:person:YOUR_PERSON_ID",
"lifecycleState": "PUBLISHED",
"specificContent": {
"com.linkedin.ugc.ShareContent": {
"shareCommentary": { "text": "Hello from MCP 🚀" },
"shareMediaCategory": "NONE"
}
},
"visibility": {
"com.linkedin.ugc.MemberNetworkVisibility": "PUBLIC"
}
}'
A 201 Created response means success.
Registering this server in ChatGPT / Claude MCP
Add this to your MCP config:
json
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{
"mcpServers": {
"linkedin_poster": {
"command": "node",
"args": [
"C:\\Users\\User\\Desktop\\mcp-linkedin-poster\\dist\\index.js"
],
"env": {
"LINKEDIN_ACCESS_TOKEN": "PASTE_TOKEN_HERE",
"LINKEDIN_AUTHOR_URN": "urn:li:person:PASTE_ID_HERE",
"LINKEDIN_VERSION": "202502"
}
}
}
}
Restart ChatGPT / Claude Desktop after saving.
Common errors & fixes
❌ Missing env LINKEDIN_ACCESS_TOKEN
.env not created
MCP config missing env
Token pasted with line breaks
❌ Invalid OAuth 2.0 Access Token (code 190)
Token expired
Wrong app
Missing w_member_social scope
Regenerate token.
❌ PowerShell header error
Use a hashtable, not a string:
powershell
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-Headers @{ Authorization = "Bearer $token" }
❌ Node cannot find dist/index.js
Run commands from the project root, not src/.
Correct:
bash
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node dist\index.js
Wrong:
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node src\dist\index.js
Security notes
Treat LinkedIn tokens like passwords
Do not commit secrets
Prefer MCP environment injection over .env in production
**
for CLAUDE
"linkedin_poster": {
"command": "node",
"args": [
"C:\\Users\\User\\Desktop\\mcp-linkedin-poster\\dist\\index.js"
],
"env": {
"LINKEDIN_ACCESS_TOKEN": "",
"LINKEDIN_AUTHOR_URN": "urn:li:person:",
"LINKEDIN_VERSION": "202502"
