Instagram MCP: publish photos, carousels and Reels

Can an AI assistant publish to Instagram through MCP?

Yes, when the assistant has an authorized publishing tool and an eligible connected Instagram account. Mellow Hub exposes those tools at https://www.mellow.world/mcp. A compatible remote MCP client can validate a post, schedule it within the owner’s delegation, and read its final destination result.

Start with the account and one actual draft. MCP is the tool connection; Instagram still decides whether the account, permissions and media can publish. This guide covers Mellow Hub. For planning your own Instagram content on iPhone or the web, see the separate Mellow planning guide.

What Instagram account do I need?

Use a professional Instagram account: Business or Creator. A personal account is not eligible for this publishing API flow. In Hub, open Channels, choose Instagram and complete the account connection yourself.

These are different authorization paths. Choose the path that matches your account setup; completing one does not grant every permission in the other. Meta’s official Instagram API collection documents the distinction. The managed connection used by Hub is described in Post for Me’s account requirements.

Stories need an additional eligibility check: Meta’s Facebook Login documentation limits Story publishing to Business accounts. A format appearing in Hub’s input rules does not establish that your account can publish it. Confirm the connected account and its delivery result before relying on that format.

Connect the assistant and check its authority

1. Connect your Instagram account in Hub. The returned channel ID identifies that connection; an Instagram username is not a substitute.
2. Add Hub’s endpoint in a client that supports remote MCP over Streamable HTTP. Follow its OAuth flow, or use an owner-created Hub key if that client supports it. Setup and availability depend on the client. Keep credentials in its secure configuration.
3. Choose the channels, mode, daily ceiling and expiry in Agents. Review mode prepares work for a person’s approval. Autopilot permits publishing within the delegation.
4. Call whoami and list_channels. Check the actual mode and use the returned Instagram channel ID. Read list_platforms for the current rules.
5. Prepare reachable media. Use register_media to inspect an existing public URL, or request_upload_url for uploading a local file. Keep the resulting URL reachable through the planned publication time.

For the full connection sequence and result contract, use the MCP workflow guide. Adding a connector or pasting a prompt alone does not authorize an Instagram account.

Choose the format before validating

Hub currently enforces a caption limit of 2,200 characters and an overall range of 1–10 media items for Instagram. Placements narrow that range. These are Hub’s enforced input rules; they can be more conservative than Instagram’s own editor.

Hub currently rejects a mixture of recognized image and video URLs in one post. Use a single media type for its carousel input. That is a Hub limitation, not a claim that Instagram itself never supports mixed carousels.

Placement behavior is documented by Post for Me. File size, codecs, aspect ratio and duration still need to satisfy Instagram. Hub’s input validator does not download and measure the file, and a URL without a recognizable extension can leave its media type unknown.

Three post inputs you can adapt

Pass one of these objects as the arguments to validate_post. Replace the sample channel ID, media URLs, caption and 2030 timestamp with your own values. The date is intentionally illustrative; use an explicit UTC Z or timezone offset. These payloads are checked against Hub’s parser and validator, using a synthetic channel. They are not live Instagram publication receipts.

{
  "channels": [
    "spc_your_instagram_channel"
  ],
  "scheduledAt": "2030-01-15T10:00:00Z",
  "caption": "A closer look at the glaze on this cup.",
  "media": [
    "https://cdn.example.com/your-cup.jpg"
  ],
  "options": {
    "instagram": {
      "placement": "timeline"
    }
  }
}

{
  "channels": [
    "spc_your_instagram_channel"
  ],
  "scheduledAt": "2030-01-15T10:00:00Z",
  "caption": "From clay to finished cup, in three stages.",
  "media": [
    "https://cdn.example.com/your-clay.jpg",
    "https://cdn.example.com/your-process.jpg",
    "https://cdn.example.com/your-cup.jpg"
  ],
  "options": {
    "instagram": {
      "placement": "timeline"
    }
  }
}

{
  "channels": [
    "spc_your_instagram_channel"
  ],
  "scheduledAt": "2030-01-15T10:00:00Z",
  "caption": "How this handle is attached.",
  "media": [
    "https://cdn.example.com/your-process.mp4"
  ],
  "options": {
    "instagram": {
      "placement": "reels",
      "shareToFeed": true
    }
  }
}

A real media URL must be reachable by the publishing service when it is fetched. Meta describes this requirement in its content publishing reference. A local path, a private drive link or an expired signed URL is not a usable replacement.

Fix the reported issue before creating the post

Read ok, issues and notes in the validation result. A successful HTTP request can still carry ok: false. The issue names the affected channel and field.

Try the free post checker before connecting an account. It uses the same input rules with sample destinations. Authenticated validation checks actual connected channels; neither result guarantees eventual provider delivery.

Schedule once and verify the Instagram result

After a valid check, call create_post with the same intended post and a stable idempotencyKey, such as ceramics-instagram-reel-slot-001. Creating is the step that prepares or schedules the actual publication. In review mode it waits for approval; in autopilot it may proceed at the chosen time. Check the current plan allowance first.

Keep the returned post ID. If the create response is lost, retry the same request with the same key. Do not generate a new key just because of a timeout. A changed post needs a new key.

Call get_post and inspect the Instagram entry in targets. Read its final status, public URL or error. A Hub post being accepted is not proof that Instagram published it. For a multi-network request, another destination may succeed while Instagram fails.

For server integrations using HTTP directly, the REST scheduling recipe gives the equivalent requests and idempotency header. For a first setup, connect your Instagram channel and validate one draft before preparing a recurring schedule.