From ChatGPT draft to Slack queue
The writing already happens in ChatGPT. With the public API or the CLI, the same conversation can create scheduled Slack messages instead of text to paste.
SlackAutomate Slack with ChatGPT
Draft Slack messages in ChatGPT, then let postqueen schedule and publish them. One conversation in, a full Slack queue out.
Quick start
Point a custom GPT action at the public API, or let agent modes that run commands use the CLI for Slack.
Custom GPT or CLI
# Custom GPT action: call the public APIPOST https://api.postqueen.ai/public/v1/postsAuthorization: your_api_key # Or in agent modes that run commands:npm install -g postqueenpostqueen posts:create --json slack-week.jsonWhat ChatGPT can run on Slack
Windows that fit Slack
Tell ChatGPT when your channels are busiest and it schedules messages into that window on Slack, day after day, without reminders.
The right channels, every time
ChatGPT lists your connected channels before it posts, so messages land exactly where they should and announcements stay consistent.
Drafts until you are ready
Ask ChatGPT for drafts only. They sit on the postqueen calendar unscheduled, so you can edit them and pick the time yourself, and nothing reaches your workspace members on Slack until you do.
Three steps to a full queue
Discover Slack
ChatGPT calls postqueen to list your connected channels and sees what Slack supports, so drafts start from real capabilities, not guesses.
Draft with ChatGPT
Give it the brief. The agent writes Slack-shaped messages and proposes publish times that match when your workspace members are around.
Check and publish
Look over the queue on the postqueen calendar and change anything you want. postqueen publishes each post at its time, and ChatGPT can pull the results after.
What Slack allows
ChatGPT reads these limits from postqueen before it composes, so a draft that would be rejected never reaches the queue.
- Message length
- Up to 40,000 characters per message through the Slack API
- Formatting
- Slack mrkdwn: bold, italics, code blocks, quotes and links
- File uploads
- Files up to 1 GB each
- Rate limit
- About one message per second per channel, with short bursts allowed
- App requirement
- The postqueen app must be installed in the workspace and invited to private channels
SlackEverything postqueen does on Slack
Scheduling, AI drafts, analytics and team roles, in one guide.
F.A.Q.
Frequently asked questions
How does ChatGPT connect Slack to postqueen?
Through the public API from a custom GPT action, or through the CLI in agent modes that execute commands. Both use the same API key and cover Slack messages end to end.
Can ChatGPT schedule Slack messages at exact times?
Yes. Give it exact slots or a rule like mornings at nine and it sets publish times on the messages it creates, keeping your channels active on a steady rhythm.
Will ChatGPT publish to Slack on its own?
Only if you ask it to. Tell it to save drafts and nothing is scheduled: the messages wait on the calendar until you set a time. Tell it to schedule, and they go out at the times you can see, which is the setup most people move to once they trust the output.
Can one brief cover Slack and other channels too?
Yes. postqueen connects 30 channels, so ChatGPT can turn the same brief into Slack messages plus adapted versions for every other channel you run.
Does ChatGPT access cost extra on postqueen?
No. The agent uses your regular API key and plan limits: unlimited posts on every plan, and channel counts from 5 on Creator up to uncapped on Ultimate.
Can I send one update to several channels or workspaces?
Yes. Select any mix of connected channels across your workspaces and postqueen delivers the message to each one. You can adjust the wording per channel before it goes out.
Can AI draft my Slack announcements?
Yes. The built-in assistant writes and rewrites messages in a tone that fits your team, and nothing publishes until you schedule it. You can also drive Slack posting from Claude Code, ChatGPT or any other agent through the MCP server and the CLI.
Ready to get started?
Queue this week's posts in minutes, or hand the whole thing to your favorite AI. postqueen keeps publishing either way.
Seven days free. Cancel in one click from settings.