LinkedIn Posting#

Overview#

Post text and images to LinkedIn via the message tool using the linkedin channel. Supports text-only posts, image posts (local files or URLs), and #BuildInPublic updates.

Prerequisites#

The linkedin channel must be configured in channels.linkedin with:

• accessToken: OAuth 2.0 token with w_member_social scope
• personUrn: Your LinkedIn person URN (e.g. urn:li:person:Abc123)

Posting Text#

Use the message tool to send a text post:

text

message send --channel linkedin --text "Your post content here"

The post goes to the authenticated user's LinkedIn feed as a public post.

Posting with Images#

Two-step process:

1. Create the image — generate or locate the image file (PNG/JPG/GIF/WebP)
2. Post with image — use message send with the --media flag:

text

message send --channel linkedin --text "Post caption" --media /path/to/image.png

Supported image sources:

• Local file paths: /Users/david/image.png
• file:// URLs: file:///Users/david/image.png
• Remote URLs: https://example.com/image.png

Image Upload Flow (internals)#

The extension handles a 3-step LinkedIn UGC API flow automatically:

1. Register upload → gets uploadUrl + asset URN
2. PUT binary to uploadUrl
3. Create UGC post with asset reference

You don't need to manage this — just provide the image path.

Best Practices#

• Always confirm post content with the owner before posting
• Keep posts concise — LinkedIn favors 150-300 word posts
• Add hashtags at the end, not inline (3-5 max)
• For #BuildInPublic: include what you built, what you learned, a visual
• Image sizing: 1200x627px for link previews, 1080x1080 for square posts
• Never post without explicit owner approval

Post Templates#

#BuildInPublic Update#

text

🚀 [What you built today]

[2-3 sentences about what it does and why it matters]

Tech stack: [list]

[Screenshot or diagram]

#BuildInPublic #[topic] #[tech]

Project Milestone#

text

✅ [Milestone achieved]

[Brief context — what, why, how]

Key learnings:
→ [Learning 1]
→ [Learning 2]
→ [Learning 3]

Next up: [what's coming]

#[project] #[topic]

Technical Deep-Dive#

text

💡 TIL: [Thing you learned]

[Explanation in 2-3 paragraphs]

[Code snippet or diagram if relevant]

#TIL #[topic] #[tech]

Troubleshooting#

ErrorCauseFix401 UnauthorizedToken expiredRe-authenticate, update channels.linkedin.accessToken403 ForbiddenMissing w_member_social scopeRe-create OAuth app with correct scopesImage upload 400File too large (>10MB)Compress image before uploadingEmpty postUrnAPI didn't return IDPost likely succeeded — check LinkedIn feed