Social posts for four networks from a topic or link

What it is

This n8n workflow writes one idea up for four networks and publishes it. You send a form with a niche or an article link, plus an optional brand color and a view of your own. From a niche, an OpenAI model suggests five post ideas and you pick one in a second form. Tavily then fetches five articles and a model condenses them into a summary. From a link, the workflow reads the page and summarizes it. Next, one model writes a caption each for Facebook, Instagram, LinkedIn and X, while four image prompts go to Kie.ai’s Nano Banana model, one picture per network. The pictures are uploaded to a Mixpost workspace, and a single Mixpost call publishes all four posts.

Who it suits

Solo founders, creators and small marketing teams that want one idea on four networks, each with its own wording and picture, without writing four posts. It assumes you already run Mixpost for your accounts or are willing to set it up.

You need more than usual here: n8n, four service keys, a community node and a Mixpost workspace with four networks connected. If Mixpost is not running yet, skip this one. The page it came from estimates 12 minutes, which assumes everything on that list exists.

Where to use it

An n8n that can install community nodes and reach OpenAI, Tavily, Kie.ai and your Mixpost.

• Your own n8n server: install the community node from its settings, then import the file
• n8n Cloud: it installs only verified community nodes, so check that this one is offered
• Your Mixpost: the pictures and the posts land in its workspace and go out from the accounts connected there
• Other networks: the order list in Sort Social Media, the four caption names in Content Writer and the versions in Create a post are the places to change

Setup

Get it saves a zip with workflow.json and Mindket’s setup notes in your downloads folder. Have these ready before you import it.

1. Install n8n-nodes-gravitysocial under Settings, Community nodes. Then create a workflow, open its menu, choose Import from File and pick workflow.json.
2. Add an OpenAI credential and select it in OpenAI Chat Model, OpenAI Chat Model1 and Content Writer.
3. Open Tavily and swap <YOUR_TAVILY_KEY> in its Authorization header for your key, keeping the word Bearer and its space.
4. Open nano-banana-api and replace YOUR_KIE_API in its api_token field with your Kie.ai key.
5. Add a Mixpost credential with your Mixpost’s base address and API token. Select it in the six Mixpost nodes: Upload FB Img, Upload IG Img, Upload Li Img, Upload X Img, Get many accounts and Create a post.
6. In the same six nodes, replace YOUR_WORKSPACE_UUID with your workspace’s UUID.
7. Select Create a post and press D to deactivate it for the first run, because the workflow publishes at once. Send a test through the form’s test address and read the captions and pictures under Executions. Then enable the node and press Publish.

The workflow reads the sorted list by position, so the workspace should hold one account of each kind and no more. Any other account sorts to the front and shifts the rest.

How to use it

Open the form from On form submission1 and choose an input method. For Topic or Niche, fill in the niche, which is required, a brand color as a name or a hex code, and your own view. The next page lists five ideas in a dropdown: pick one. For Article URL, paste the link and fill in the same two optional fields, and there is no second page. The run then summarizes, writes, draws, uploads and publishes. The images wait one minute each before they are fetched.

Example

A form entry on the topic path:

Choose your input method: Topic or Niche
Enter your niche/topic: Home espresso
Brand color (name or hex code): burnt orange
Share your personal insights or opinion: A good grinder matters more than the machine.

Generate Post Ideas returns five lines and the next page offers them in the dropdown Select one topic from below. After your pick, Tavily finds five articles and the summary model returns a title and a summary. Content Writer then returns the four captions:

{
  "facebook": "…",
  "instagram": "…",
  "linkedin": "…",
  "twitter": "…"
}

The rules in its system message shape each one. Facebook is informal and ends on a question. Instagram uses emojis, short lines and a few hashtags, LinkedIn drops the emojis and closes with a prompt for discussion, and X takes a bold, curiosity-driven stance. Your opinion is woven into all four. On the link path, Facebook, LinkedIn and X also point to the source, and Instagram never does.

For newcomers and experts

If you are new. n8n draws a workflow as boxes joined by lines, and each box, a node, does one job. A credential is a key n8n keeps for you and hands to the node you pick it in. A community node comes from someone outside n8n, so n8n cannot open this file until the node is installed. Mixpost is a tool that schedules and publishes posts to your social accounts, and it is where the four networks are connected.

For experts. The workflow trusts the order of several lists, so keep them as they are if you rewire it.

Image generation is asynchronous: createTask starts it, a fixed one-minute wait follows and recordInfo is asked once. A picture that takes longer leaves its result empty, and Content Setup stops there.

Good to know

This workflow publishes for real and costs money on every run.

• It posts at once: Create a post uses schedule_now, and no step asks you to approve the text or the pictures. Text drawn inside an AI picture can be misspelled, so run the first batches with that node deactivated
• Billing: OpenAI, Kie.ai and, on the topic path, Tavily each bill their own part
• Facts: the summaries come from pages a model read, and nothing checks them before they go out in your name
• The article path: it fetches the page with browser-like headers, and a site that blocks that or builds its text in the browser may give the summary little to work with
• Open form: once it is published, anyone with the form’s address can make your accounts post, so turn on the form trigger’s basic authentication or keep the address private
• Keys: the Tavily and Kie.ai keys sit in node fields, not in credentials, so they travel with any export of the workflow
• Community node: n8n-nodes-gravitysocial must be installed before the file opens
• A repair: the page’s copy of the file had lost the backslashes in the Code and Clean HTML patterns and in three line breaks of Content Writer. That broke the idea list and the page cleaning. Mindket put them back
• Credentials: the JSON holds none, and nothing from its author’s account