Description
I want to schedule social media posts with video (e.g. .mp4) or image attachments through the MCP interface. The post should be published on platforms like Facebook and Instagram via the tool POSTIZ_SCHEDULE_POST, using providerId values like cmbmh43360001qehe9kk43v4e.
I'm sending prompts via ChatGPT and DeepSeek, and automating the flow through n8n.
Environment:
Ubuntu 22.04 VPS
Docker Compose installation of Postiz
Custom domain: postiz.attendify.pl
Browser: Chrome
MCP: enabled and exposed at port 8000
Prompt source: OpenAI (ChatGPT-4) and DeepSeek LLM
JSON sent through n8n → HTTP Request node
Changed:
Nothing was changed — no updates, no config modifications.
Media never worked, neither video (.mp4) nor images (.jpg/.png) are attached, even though they are present in the payload.
Results:
Post is successfully scheduled
Text appears correctly
No errors in response (Post created successfully...)
But no media is attached (image/video silently ignored)
Backend logs do not show any attempt to fetch/download the media
Example payload sent to
{
"query": {
"type": "scheduled",
"configId": "SCmwcCLzoY",
"generatePictures": false,
"date": "2025-06-09T04:34:01Z",
"providerId": "cmbmh43360001qehe9kk43v4e",
"posts": [
{
"text": "Czemu mleko bananowe nie występuje naturalnie?",
"images": [
"https://www.papytane.com/mp4/boiteame.mp4"
]
}
]
},
"tool": {
"name": "POSTIZ_SCHEDULE_POST",
"description": ""
}
}
Let me know if there's an alternative schema that supports media as content, media, or attachments, or if media links should be formatted differently.
Thanks!