Post to Instagram from ChatGPT

How it works

1. ChatGPT calls list_channels to find your Instagram channel.
2. It calls get_channel_rules to learn the Instagram limit, media needs and settings.
3. It writes the post and runs check_post, which returns any rule problems.
4. It picks a time with find_free_slot if you did not give one, shows you the post, and calls schedule_post after you say yes.

Instagram rules ChatGPT follows

• Every post needs at least 1 photo or video. Upload it first with upload_media_from_url.
• Up to 2,200 characters and 30 hashtags. Carousels take up to 10 items.
• Photos must have a ratio between 4:5 and 1.91:1.
• A Reel needs exactly 1 video. Stories are posted without the caption.

Rule summary from the Instagram connector: Needs at least 1 photo or video. Max 2200 characters, max 30 hashtags. Up to 10 items in a carousel. Photos must be JPEG with a ratio between 4:5 and 1.91:1. Follow-up comments are posted as comments (text only).

Rule summary from the Instagram connector: For Business or Creator accounts that sign in with Instagram. No Facebook Page needed. Needs at least 1 photo or video. Max 2200 characters, max 30 hashtags. Up to 10 items in a carousel. Photos must be JPEG with a ratio between 4:5 and 1.91:1. Follow-up comments are posted as comments (text only).

Instagram settings the agent can use

These go in channels[].settings of schedule_post. ChatGPT learns them from get_channel_rules, so you can just describe what you want.

Instagram works with both sign-in types: a Business or Creator account through Facebook, or Instagram login without a Facebook Page. The rules are the same.

Example prompts for Instagram

• "Upload this image URL and schedule it as an Instagram post tomorrow at 19:00 with a caption and 10 relevant hashtags."
• "Make a carousel from these 5 photo links, with a caption that tells the story in order."
• "Post this video as a Reel and add @partnerbrand as a collaborator."
• "Which Instagram posts had the most reach this month?"
• "Write 3 caption options for this photo and let me pick 1 before scheduling."

What the call looks like

You never have to write this yourself. It shows what ChatGPT sends to schedule_post for Instagram, with real setting keys:

{
  "type": "schedule",
  "date": "2026-10-01T09:30:00+05:30",
  "content": "Your Instagram text",
  "media": [
    "MEDIA_ID"
  ],
  "channels": [
    {
      "channelId": "YOUR_INSTAGRAM_CHANNEL_ID",
      "settings": {
        "format": "Reel",
        "collab": "@partnerbrand"
      }
    }
  ],
  "thread": [
    {
      "content": "First comment",
      "delay": 5
    }
  ]
}

Set up ChatGPT

Add Postozo to ChatGPT as a custom app in developer mode. Then ask ChatGPT to plan, write and schedule posts on your channels. Connection: your personal key URL. Full steps are on the ChatGPT setup page. Your Instagram account must be connected in Postozo first: see the Instagram scheduler.

Also works with Claude and Cursor.

Tips for Instagram posts written with ChatGPT

• Tell ChatGPT who the post is for and what you want people to do. "Write a Instagram post for small shop owners that asks them to book a demo" works better than "write a post".
• Start the chat with a few lines about your tone and the words to use or avoid. ChatGPT writes the text itself, so it needs this to sound like you.
• Ask for 2 or 3 versions and pick 1. It is faster than asking for changes 5 times.
• Say "save as drafts" when you want to check the posts on the calendar before they are scheduled.
• Add 1 detail only you know, like a real number from your business or a customer question. It makes the post yours.