linkedin-poster

name	linkedin-poster
description	Compose and publish LinkedIn posts (text, articles, images) via the LinkedIn API. Use when user wants to draft, preview, or publish content to LinkedIn.

LinkedIn Poster

Post content to LinkedIn directly from Claude Code. Supports text posts, article shares, and image posts.

Prerequisites

Before first use, the user needs:

1. LinkedIn Developer App at https://developer.linkedin.com/
2. Products enabled: "Share on LinkedIn" + "Sign In with LinkedIn using OpenID Connect"
3. App verification completed (required for w_member_social scope)
4. Environment variables set:
   • LINKEDIN_ACCESS_TOKEN — OAuth2 Bearer token
   • LINKEDIN_PERSON_ID — User's LinkedIn person URN ID (numeric, from /v2/userinfo)

Getting Your Person ID

curl -s -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  https://api.linkedin.com/v2/userinfo | jq -r '.sub'

Getting an Access Token

Use the 3-legged OAuth2 flow:

1. Direct user to: https://www.linkedin.com/oauth/v2/authorization?response_type=code&client_id=YOUR_CLIENT_ID&redirect_uri=YOUR_REDIRECT&scope=openid%20profile%20w_member_social
2. User authorizes, LinkedIn redirects with ?code=AUTH_CODE
3. Exchange code for token:

curl -X POST https://www.linkedin.com/oauth/v2/accessToken \
  -d "grant_type=authorization_code&code=AUTH_CODE&client_id=CLIENT_ID&client_secret=CLIENT_SECRET&redirect_uri=REDIRECT_URI"

4. Token expires in 60 days. Refresh before expiry.

Capabilities

1. Text Post

Simple text update to the user's LinkedIn feed.

curl -s -X POST https://api.linkedin.com/v2/posts \
  -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -H "LinkedIn-Version: 202503" \
  -H "X-Restli-Protocol-Version: 2.0.0" \
  -d '{
    "author": "urn:li:person:'"$LINKEDIN_PERSON_ID"'",
    "commentary": "Your post text here",
    "visibility": "PUBLIC",
    "distribution": {
      "feedDistribution": "MAIN_FEED",
      "targetEntities": [],
      "thirdPartyDistributionChannels": []
    },
    "lifecycleState": "PUBLISHED"
  }'

2. Article Share

Share a URL with commentary.

curl -s -X POST https://api.linkedin.com/v2/posts \
  -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -H "LinkedIn-Version: 202503" \
  -H "X-Restli-Protocol-Version: 2.0.0" \
  -d '{
    "author": "urn:li:person:'"$LINKEDIN_PERSON_ID"'",
    "commentary": "Check out this article!",
    "visibility": "PUBLIC",
    "distribution": {
      "feedDistribution": "MAIN_FEED",
      "targetEntities": [],
      "thirdPartyDistributionChannels": []
    },
    "content": {
      "article": {
        "source": "https://example.com/article",
        "title": "Article Title",
        "description": "Brief description of the article"
      }
    },
    "lifecycleState": "PUBLISHED"
  }'

3. Image Post

Upload an image then post it. Two-step process.

Step 1 — Initialize upload:

curl -s -X POST https://api.linkedin.com/v2/images?action=initializeUpload \
  -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -H "LinkedIn-Version: 202503" \
  -H "X-Restli-Protocol-Version: 2.0.0" \
  -d '{
    "initializeUploadRequest": {
      "owner": "urn:li:person:'"$LINKEDIN_PERSON_ID"'"
    }
  }'

Response gives uploadUrl and image URN. Save both.

Step 2 — Upload binary:

curl -s -X PUT "$UPLOAD_URL" \
  -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  --upload-file /path/to/image.jpg

Step 3 — Create post with image:

curl -s -X POST https://api.linkedin.com/v2/posts \
  -H "Authorization: Bearer $LINKEDIN_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -H "LinkedIn-Version: 202503" \
  -H "X-Restli-Protocol-Version: 2.0.0" \
  -d '{
    "author": "urn:li:person:'"$LINKEDIN_PERSON_ID"'",
    "commentary": "Image caption here",
    "visibility": "PUBLIC",
    "distribution": {
      "feedDistribution": "MAIN_FEED",
      "targetEntities": [],
      "thirdPartyDistributionChannels": []
    },
    "content": {
      "media": {
        "id": "'"$IMAGE_URN"'"
      }
    },
    "lifecycleState": "PUBLISHED"
  }'

Process — When User Says "Post to LinkedIn"

1. Check env vars: Verify LINKEDIN_ACCESS_TOKEN and LINKEDIN_PERSON_ID are set. If not, guide setup.
2. Draft content: Help user compose the post. Offer to refine tone, add hashtags, optimize length.
3. Preview: Show the user exactly what will be posted. Include post type, text, any URLs/images.
4. Confirm: ALWAYS ask for explicit confirmation before publishing. Never auto-post.
5. Publish: Execute the appropriate curl command.
6. Report: Show success/failure, post URN if successful.

Content Guidelines

• Character limit: 3,000 characters for post text
• Hashtags: 3-5 relevant hashtags, placed at end of post
• Best engagement: Posts with 1,200-1,500 characters perform best
• Line breaks: Use \n for formatting. Short paragraphs improve readability.
• Emojis: Use sparingly and only if user's style includes them
• Images: JPG/PNG, max 10MB, 1200x627px recommended for article thumbnails

Error Handling

Code	Meaning	Action
401	Token expired or invalid	Guide user to refresh token
403	Missing scope or unverified app	Check app products and verification
422	Invalid post content	Check field formats, character limits
429	Rate limited	Wait and retry with backoff

Visibility Options

• PUBLIC — visible to everyone
• CONNECTIONS — visible to 1st-degree connections only

Pass as the visibility field value.

Rate Limits

LinkedIn does not publish exact numbers. General guidance:

• Stay under ~100 API calls/day
• Space posts at least 10 minutes apart
• Monitor via Developer Portal analytics tab
• Handle 429 responses with exponential backoff