AI agent for social media: what it does on its own and what you decide

Search for “AI agent for social media” and most of what you get (as of September 2026) is guides on how to build one and listicles of tools. Search for “AI social media manager” and some of the results are job listings, because it’s also a job title. This page is about the software: what an AI agent for social media does in a normal working week, shown with the one we built, Mark. What it does on its own, what waits for your approval, and what it should never do without you.

An assistant that drafts, or an agent that does the work

An assistant hands you text. You copy it, paste it into the tool you schedule with, pick a time, and then answer the comments one by one. Metricool’s assistant, for example, drafts copy with an allowance of 5 to 35 credits per brand a month (checked September 25, 2026). It helps, but the work is still yours.

An agent works where things happen. It reads your calendar, what you’ve already published, your numbers and your inbox, does the whole task, and stops to ask you at the steps that matter.

What an AI agent for social media does in a week

Here’s a week at a neighborhood coffee shop that runs Instagram and TikTok on HeyMark:

1. Plans. On Monday you ask Mark for the week’s five posts. It checks how the last ones did and leaves the drafts on the calendar. The idea, the script and the caption live on the same post, with its status, date and owner.
2. Writes in your voice. When you connect your accounts, HeyMark pulls in what you’ve already published, and Mark learns your voice from it. If the coffee shop writes short and says “the pastry case” instead of “our products”, that’s how the caption comes out.
3. Schedules and publishes. You review the drafts, schedule them, and they go out on time. What you built for Instagram you duplicate for TikTok in one click, without re-uploading the video.
4. Replies. On Wednesday someone asks under a reel whether you’re open Sunday, and Mark answers in the coffee shop’s voice. Anyone who comments “MENU” gets the menu by DM from a keyword rule, which spends no credits.
5. Hands off to a person. On Thursday a complaint comes in about a wrong order. That conversation is escalated for human attention and, if you want, you pause the AI there while you sort it out.
6. Reports. On Friday you ask how the week went. It answers with your numbers: which post took most of the reach and which ones stayed within your normal range.

What it does on its own and what needs your approval

An agent that publishes without asking is a liability, and one that asks about everything saves you nothing. Inside the app, Mark proposes the caption and you apply it; each post’s activity log records who did what. When the agent works from Claude or ChatGPT, the rule is written into HeyMark’s MCP server:

Scheduling runs directly, but scheduling is also publishing later: approve the copy and the time before you ask for it.

Your own assistant can be the agent too

You don’t have to choose between Mark and the assistant you already use. HeyMark has a public MCP server (https://mcp.heymark.ai) that connects to Claude, ChatGPT, Claude Code or Codex. You sign in with your account, with no keys to generate, and your assistant sees what you see and nothing else. It’s free on every plan; AI actions spend their credits as usual. In ChatGPT, creating or publishing requires developer mode. The setup is on Claude and HeyMark and ChatGPT and HeyMark.

To try the whole loop, ask for a week of work:

Use HeyMark to review what I published in the last 30 days and how each post performed.

Based on that, propose 5 posts for next week. For each one: format, idea, caption in my brand's voice and a suggested day. Save them as drafts on the calendar, without scheduling or publishing them.

Then check the inbox and tell me which conversations are waiting for a reply and which ones are escalated to a person. If you suggest replies, show me the text and wait for my approval before sending anything.

What an agent shouldn’t do alone

• Publish without review. Publishing now requires your approval, and what goes out is your call.
• Answer a complaint, a legal question or a crisis. That’s where people can tell a machine is replying. Those conversations are escalated to a person, and you can pause the AI in any conversation. More in AI comment replies.
• Delete comments. Automatic moderation holds comments for review, and deleting one from the platform requires your approval.
• Make up numbers. An agent that can’t find a figure should say so. Ask it to read HeyMark before concluding and to flag what’s a hypothesis.

How to get started

1. Connect your accounts

   Instagram, TikTok, Facebook, LinkedIn and YouTube, one account per network on each brand. HeyMark pulls in what you’ve published, and Mark understands your voice from there.

2. Ask Mark for your first week

   Review the drafts it leaves on the calendar, fix anything that doesn’t sound like you, and schedule them.

3. Put the inbox to work

   Turn on AI replies and a keyword rule for the question you always get, like an Instagram DM automation for comments.

4. Connect your assistant, if you use one

   Paste the MCP URL into Claude or ChatGPT and approve the access.

Creator costs $12 USD a month (1 brand, 1 person, 500 AI credits) and Company $30 USD a month (3 brands, 5 people, 3,000 credits and access by area). Each Mark turn uses 10 credits, and each AI reply or DM uses 1. Platform, for agencies and large teams, is quoted.