Connect Instagram to ChatGPT to post and reply

A clothing store types into ChatGPT: “Check which carousels did best for us in September and build one for the new collection.” ChatGPT looks at the real posts on its Instagram account, proposes the slides and leaves a draft on the brand’s calendar. That’s what you get when you connect Instagram to ChatGPT through HeyMark: ChatGPT stops being the thing that writes while you copy and paste, and works on your actual account, with your calendar, your metrics and your inbox of comments and messages.

The connection runs on HeyMark’s MCP server. MCP is the standard an assistant uses to work with outside tools, and there’s nothing to code here: you paste a URL, sign in with your HeyMark account, and ChatGPT sees what you see and nothing else.

What ChatGPT can do once Instagram is connected

Here’s what you can ask for, and what waits for your approval before it touches your account:

It can also hide comments or set up a rule that replies in public and sends a DM to anyone who comments a keyword (that’s how Instagram DM automation works), always with your approval. And the same connection covers TikTok, LinkedIn, Facebook and YouTube.

How to connect Instagram to ChatGPT, step by step

You need a HeyMark account with Instagram connected under My accounts (the trial runs 14 days) and ChatGPT in your browser. You only set this up once.

1. Copy HeyMark's MCP URL

   In HeyMark, open Connectors in the lower left corner and select Copy URL. It’s the same for everyone: https://mcp.heymark.ai. The URL is public; what protects your account is the authorization you complete later.

2. Turn on developer mode

   In ChatGPT, open Settings and go to Apps (your interface may call it Plugins, or Apps and Connectors). At the bottom, under the advanced settings, turn on Developer mode. ChatGPT warns you that custom apps can access external services.

   

3. Create the HeyMark app

   Open Apps from ChatGPT’s sidebar and select Create app. Enter HeyMark as the name, paste the URL into MCP server URL, confirm that you understand the warning and select Create.

   

4. Authorize with your HeyMark account

   Select Sign in with HeyMark and approve the access. You land back in ChatGPT with HeyMark in your apps. There are no keys to copy: the connection uses OAuth.

   

5. Allow the actions

   In Settings, open Apps, select HeyMark and choose Allow all actions under Permissions. Only do this for the connection you created from your own account. The sensitive steps still wait for you: HeyMark asks for a preview before publishing now or replying.

6. Turn it on in a chat

   Open a new chat, select +, type Hey and pick HeyMark. Before writing your message, check that its name shows in the text field. To test it, ask it to list your brands.

Every screen and the most common problems are in the guide Carousels in 1 minute with ChatGPT + HeyMark.

Can ChatGPT post to Instagram?

Yes, and it goes past the caption: it creates the post, schedules it and publishes it, whether it’s a Reel, a story, a feed post or a carousel. Ask for the draft first and check the caption, account and date. Scheduling runs right away and the post goes out on its own at that time; publishing now goes through a preview you approve first.

One detail with carousels: the images ChatGPT generates stay in the chat. To get them into the post, upload them in HeyMark; in clients that support inline MCP apps, HeyMark can also open its media picker right there.

Create a carousel for my brand using the style of the posts that performed best in my feed. Use HeyMark to review what I’ve already published and its metrics, and propose a six slide structure in a vertical 4:5 format.

Create a HeyMark draft for Instagram with this carousel’s caption. Show me the caption, the target account and the date before going further. Once I approve, schedule it for Thursday at 7:00 p.m. in my time zone.

Your numbers and your inbox, from the chat

For metrics, ChatGPT reads the same things you see in HeyMark: followers, views and engagement against the previous period, the reach of each post, and the age, gender, country and city of your audience. In the inbox, it tells you which conversations are waiting on an answer and drafts each reply in your brand’s voice. Nothing goes out until you approve the preview.

Check my HeyMark inbox and tell me which Instagram comments and messages still have no reply. Suggest a reply for each one in my brand’s voice and don’t send any until I approve its preview. If one is a complaint, don’t reply: flag it for me.

Limits worth knowing

• No developer mode, no actions. ChatGPT only creates, schedules, publishes or replies with that mode on. It labels the mode high risk because it lets you add unverified connectors; use it for connections you know, like the one you create from your own HeyMark account.
• ChatGPT’s rules are ChatGPT’s. OpenAI decides which plans and workspaces allow custom apps, how much you can use them and what the subscription costs. Check their help article on developer mode.
• Cost on HeyMark. The MCP adds no cost on any plan; actions keep your plan’s limits and AI credits. There’s no free plan: a 14-day trial, then from $12 USD a month.
• Five networks. HeyMark publishes to Instagram, TikTok, LinkedIn, Facebook and YouTube. It doesn’t publish to X, Pinterest, Threads, Bluesky or Google Business Profile.

When something else fits better

• If you only want ideas and captions to copy by hand, you don’t need to connect anything: ChatGPT already writes without HeyMark.
• If you’d rather not turn on developer mode, Claude adds HeyMark as a custom connector from Settings, with no such step.
• If you work in a terminal with local files, Claude Code or Codex upload files from your computer straight into the post.
• If you already use Metricool and only need to schedule and read metrics, it has had an official ChatGPT connector since September 10, 2026. Of its 27 documented tools, 2 write (they schedule posts and edit scheduled ones); replying to comments or DMs isn’t among them, as checked on September 25, 2026.

To see what the MCP does on Instagram, tool by tool, go to the Instagram MCP server page.