# Post to Instagram from n8n with an AI agent

Source: https://postgale.com/guides/n8n/instagram

Yes, an n8n workflow can post to Instagram through Postgale. Attach an MCP Client Tool node pointed at https://postgale.com/mcp to an n8n AI Agent node (or call the REST API from an HTTP Request node) with a Postgale API key, connect your Instagram account in Postgale once, and the agent can images, Reels, Stories, carousels, comments and DMs. A person can be required to approve every post, reply and message before it goes out.

## Can n8n post to Instagram?

Postgale is the secure layer for AI agents on social media. MCP (Model Context Protocol) is the open standard that lets AI assistants such as Claude and Cursor use outside tools. An MCP server is what they connect to. n8n does not reach Instagram on its own; with Postgale connected it gets tools for the Instagram accounts you connected and nothing else.

| Task | What Postgale does |
| --- | --- |
| Publish | Single image, Reel, Story (image or video) and carousels of 2–10 items; captions up to 2,200 characters and 30 hashtags; optional first comment, collaborators, location, user tags and alt text. |
| Schedule | Give `scheduledFor` and a worker publishes at that time; the result arrives on your webhook as post.published or post.failed. |
| Comments | List comments and replies, reply, hide, delete, and turn comments off on a post. |
| Mentions | Read the posts the account was tagged in. |
| Direct messages | List conversations, read messages and reply (text up to 1,000 characters or an attachment) inside Meta’s 24-hour window. |
| Insights | Post insights (reach, likes, comments, shares, saves, views; Reel watch time), account insights, follower demographics and online-followers hours. |

## What do you need?

- An Instagram professional account (Business or Creator). Personal accounts cannot publish through Meta’s API.
- A Postgale workspace, and the account owner signing in once with Instagram login.
- An image or video on a public HTTPS URL. Images must be JPEG. Upload a file with `upload_media` to get a URL, or bring your own.
- n8n, set up as below (Workflows with the HTTP Request or MCP Client Tool node).

## Step 1: connect your Instagram account

1. Create a Postgale workspace and open Dashboard → Accounts.
2. Choose Connect Instagram and sign in with the account you own, on the platform’s own page. Postgale stores the tokens encrypted and refreshes them.

## Step 2: connect n8n to Postgale

| Use | Node | When |
| --- | --- | --- |
| Fixed steps | HTTP Request | Your workflow knows what to post (a new blog post, a product update, a form submission). Call `POST /api/v1/posts` with the content and the account ids. |
| An agent decides | MCP Client Tool attached to an AI Agent node | The model reads the input (an inbox, a brief, a trigger) and chooses among Postgale’s tools: list accounts, upload media, create or schedule posts, read and reply to comments and messages. |

## How do I set up the MCP Client Tool node?

1. In Postgale, open Dashboard → API keys, create a key and copy it (it starts with `sk_` and is shown once). Connect the social accounts the agent may use under Dashboard → Accounts.
2. Add an AI Agent node with your model, and attach an MCP Client Tool node to it.
3. In the MCP Client Tool node set the endpoint to `https://postgale.com/mcp`, the transport to HTTP streamable, and authentication to a Bearer or Header Auth credential carrying `Authorization: Bearer sk_…`.
4. Leave the tool list on “all” to start, or select only the read-only tools until you trust the workflow.
5. Give the agent a system prompt that states the account ids it may use and whether it must save drafts or may schedule.

> Ask your agent: “You manage the Northline accounts in Postgale (ids in the context). For each new blog post in the input, draft one Instagram caption with the cover image and one Threads post, save them as drafts, and reply with the Postgale post ids.”

## How do I set up the HTTP Request node?

1. In Postgale, open Dashboard → API keys, create a key and copy it (it starts with `sk_` and is shown once). Connect the social accounts the agent may use under Dashboard → Accounts.
2. In n8n create a credential of type Header Auth with name `Authorization` and value `Bearer sk_…` (your key).
3. Add an HTTP Request node: method POST, URL `https://postgale.com/api/v1/posts`, authentication Header Auth with that credential, body type JSON:

HTTP Request body (JSON):
```json
{
  "content": "{{ $json.caption }}",
  "scheduledFor": "{{ $json.publishAt }}",
  "platforms": [
    {
      "accountId": "acc_instagram",
      "platformSpecificData": {
        "mediaUrl": "{{ $json.imageUrl }}"
      }
    },
    {
      "accountId": "acc_threads"
    }
  ]
}
```

1. Get the account ids once with a GET to `https://postgale.com/api/v1/accounts` using the same credential.
2. Optional: send an `x-request-id` header built from your trigger id, so a re-run of the workflow returns the same post instead of a duplicate.
3. To know when the post is live, add a Webhook node and register its URL in Postgale (Dashboard → Webhooks); Postgale sends post.published or post.failed, signed with HMAC-SHA256.

## What can I ask the agent to do on Instagram?

Check the connection first: “Which Instagram accounts are connected in Postgale?” Then, in plain language:

> Ask your agent: “Post this product photo to our Instagram tomorrow at 9am Eastern. Caption: “The fall drop is live.” Put the hashtags in a first comment.”

> Ask your agent: “Turn these five photos into an Instagram carousel with a short caption. Save it as a draft.”

> Ask your agent: “Read today’s comments on our latest Instagram post and draft replies to the sizing questions. Don’t send them yet.”

POST /api/v1/posts (Instagram):
```json
{
  "content": "The fall drop is live. Shipping Thursday.",
  "scheduledFor": "2026-10-22T13:00:00Z",
  "platforms": [
    {
      "accountId": "acc_instagram",
      "platformSpecificData": {
        "mediaUrl": "https://media.example.com/fall-drop.jpg",
        "firstComment": "#fall #wool #madeinusa"
      }
    }
  ]
}
```

## Which Instagram rules does Postgale enforce?

- Media is required. A text-only Instagram post is rejected before anything reaches Meta.
- Images must be JPEG on a public HTTPS URL; Meta downloads them. Captions are cut off at 2,200 characters and 30 hashtags.
- Carousels take 2 to 10 items, images and videos mixed. Reels and carousels are processed by Meta asynchronously; Postgale polls the container and publishes when it is ready.
- Meta limits how many posts an account can publish per 24 hours. Postgale reads the current quota before every publish instead of guessing.
- Login tokens last 60 days. Postgale refreshes them during the last week automatically, so an account that posts rarely does not silently expire.
- Replies to direct messages are only allowed within 24 hours of the person’s last message (7 days with Meta’s human-agent tag). Outside that window Postgale returns a clear error and sends nothing.

> Comments and messaging depend on the permissions Meta has approved for the connected app. When a permission is missing, Postgale answers with missing_permission instead of failing quietly.

## How do I keep a person in the loop?

- Approval: tick “Hold posts from this app for approval” when you sign in, or in the Postgale dashboard require approval for the API key the agent uses (or for the whole workspace, or one account). Posts then wait as pending approval; comment replies and moderation, direct messages, WhatsApp sends and edits to live posts wait in the same queue. A person approves, edits or rejects each one in Dashboard → Approvals; the agent’s own key or sign-in cannot approve.
- Tool annotations: every Postgale tool declares whether it only reads, writes, or publishes live, deletes or spends. Clients that honour annotations ask before destructive tools run.
- Audit log: every write the agent makes is recorded with the key or the connected app, the action and the time.
- Revoking: each sign-in appears under Dashboard → Connected apps and each key under Dashboard → API keys; either can be revoked at any time.

## What can’t an agent do on Instagram through Postgale?

- Connect a personal Instagram account. Meta’s API publishes only for Business and Creator accounts.
- Delete a published Instagram post. Meta’s API does not allow it; Postgale returns not_supported.
- Start a new direct-message conversation. On Instagram an agent can only reply to people who wrote first.
- Post without an image or video.

## Questions

### Can an n8n AI agent post to Instagram?

Yes, an n8n workflow can post to Instagram through Postgale. Attach an MCP Client Tool node pointed at https://postgale.com/mcp to an n8n AI Agent node (or call the REST API from an HTTP Request node) with a Postgale API key, connect your Instagram account in Postgale once, and the agent can images, Reels, Stories, carousels, comments and DMs. A person can be required to approve every post, reply and message before it goes out.

### Does an n8n AI agent see my Instagram password or tokens?

No. The account owner signs in on the platform’s own page once, and Postgale stores the resulting tokens encrypted. An n8n AI agent only holds a Postgale API key or sign-in, which you can revoke at any time.

### Can I approve what an n8n AI agent sends to Instagram before it goes live?

Yes. Turn on approval for the API key it uses, the account or the whole workspace. Posts, replies and messages then wait in the Postgale dashboard until a person approves, edits or rejects them; an n8n AI agent’s own access cannot approve.

### Can an n8n AI agent schedule Instagram posts?

Yes. Ask for a date and time; Postgale stores the post as scheduled and publishes it then, and reports the result (post.published or post.failed) on your webhook and in get_post.

## Related

- [n8n guide](https://postgale.com/guides/n8n)
- [Instagram for AI agents](https://postgale.com/integrations/instagram)
- [n8n and Facebook](https://postgale.com/guides/n8n/facebook)
- [n8n and Threads](https://postgale.com/guides/n8n/threads)