How to Use posterly with OpenClaw: Skill in WhatsApp to First Approved Schedule

OpenClaw is the agent you already message from WhatsApp, Telegram, Slack, or Discord. You do not want a desktop app just to queue a Reel. That is what the posterly skill is for.

Skill first. The same POSTERLY_API_KEY works for the skill, MCP, and REST. If the runtime can speak MCP, point it at https://www.poster.ly/api/mcp as well. If it cannot, the skill falls back to REST with that key. Chat attachments in WhatsApp or Telegram are not MCP uploads.

This is a new-user walkthrough, from npx skills add to the first approved schedule. The long encyclopaedia is the OpenClaw guide. Fields sit on poster.ly/openclaw.

Two layers, any chat app

• OpenClaw is the chat-app layer. You talk where your team already talks.
• posterly is accounts, media, the queue. Buy Starter + API in one checkout ($10 a month). Agency API is $29 a month on Agency. See pricing.

A photo you send on WhatsApp does not become upload_media. For a real file, OpenClaw must call create_media_drop, you open https://www.poster.ly/drop/<token> in the phone browser, then list_media. Why: Solving the 4MB MCP limit.

1. Install the skill, set the key

npx skills add awpthorp/posterly-agent
export POSTERLY_API_KEY=pst_live_your_key_here

Public skill repo: github.com/awpthorp/posterly-agent. The skill teaches OpenClaw when to use MCP and when to fall back to REST. It does not collect cards or social passwords.

If you do not have a key yet, message OpenClaw:

You: Set up posterly as my social scheduling agent. I do not have an account. Do not post anything.

OpenClaw: Confirm the email. Pay and set a password in the browser. I will not take the card.

2. Agent-led signup (you still pay in the browser)

start_signup, checkout, get_signup_session, password in posterly. Same contract as agent signup. Then export the key on the machine that runs OpenClaw. WhatsApp never sees pst_live_... if you can avoid it. Prefer env on the host.

You: Run whoami. Do not post.

OpenClaw: Authenticated. No social accounts yet. Instagram or LinkedIn?

Founder newsletter

Launch with Alex

Building companies from Dubai. Field notes from running more than one, and the decisions that paid off.

Join the list (opens in a new tab)

3. Connect a network from the chat app

OpenClaw sends connect_url. You open it on the phone, approve Meta or LinkedIn, come back to WhatsApp. 30 minutes. If the session expires, ask for a new one. Do not paste Facebook passwords into Telegram.

4. Draft, validate, then say send

WhatsApp is short. The tools are not.

1. Draft.
2. validate_post.
3. Preview.
4. You reply yes to that caption and time.
5. create_post with confirm: true.

You: Draft LinkedIn for Thursday 10:00 UK. Validate. Do not create.

OpenClaw: validate_post passed. No row yet. Reply schedule it to queue.

You: Schedule it.

OpenClaw: Scheduled. View in Posterly: [link]

A group chat "yes" to someone else's joke is not confirmation. Prefer a DM with OpenClaw for writes.

5. Media from WhatsApp

Do not forward the Reel into the chat and expect a schedule.

You: create_media_drop, send the /drop/ link, wait, list_media, then validate_post.

HEIC is rejected. Export MP4 or JPEG. Plan caps still apply.

posterly

Schedule smarter with AI

AI captions, 18 platforms, plans from $7/mo

Start Free TrialSee how it works

6. After the first post

Batch, brand voice, analytics. If MCP is available on the runtime, prefer it over REST for the same key. The skill already knows that split.

7. Where this usually breaks

• Key only in the chat, never in env. Rotate it, put it on the host, do not leave pst_live_ in a Slack scrollback.
• WhatsApp attachment as media. Not MCP. Use the drop page.
• Group-chat confirmations. Confirm in a DM.
• Skipped confirm flag. Tool refuses.
• Stale OAuth. New session.

Start with the skill

npx skills add awpthorp/posterly-agent, set the key, walk agent signup if you are new, then approve one validated post from WhatsApp. The short OpenClaw setup page has skill, MCP, and REST side by side.

You keep the chat app. posterly keeps the queue. Nothing publishes until you say send.