Tools

What You'll Build

A pipeline where one row in a content table becomes a finished, published Instagram carousel, with no designer and no manual posting.

A builder named markyonolan shared the full workflow after spending a few weeks on it. His framing is the honest one: "The AI part is the easy bit. The hard part is everything between 'I have 5 generated images' and 'Instagram accepts them as one carousel.' That is where I lost a week, and what this post is really about."

You drop ideas into a table. The pipeline picks an unpublished one, writes the slide prompts and the caption, generates the images, hosts them correctly, and publishes the carousel to Instagram. Then it marks the row as published and moves on. You show up to a feed that posts itself.

Why This Works

Carousels are the highest-effort, highest-reach format on Instagram, which is exactly why most small businesses post them rarely or not at all. Each one means an idea, a designer or an afternoon in Canva, copy, and remembering to post. So it does not happen, and the account goes quiet.

The bottleneck was never the ideas. It was the production line between an idea and a published post. This pipeline is that line, automated end to end. The reach format that used to cost you an afternoon now costs you a row in a spreadsheet. Consistency, the thing the algorithm actually rewards, stops depending on whether you felt like making a post that day.

Prerequisites

Step-by-Step Setup

Step 1: Pull an Unpublished Idea

The workflow reads one row from your content Data Table where the published flag is not set. That row is the whole input: a topic or an angle.

Step 2: Expand the Idea With GPT-4.1

GPT-4.1 takes the idea and returns structured JSON: a set of image prompts (one per slide) plus the caption. Asking for structured JSON, not prose, is what lets the rest of the workflow loop over the slides reliably.

Step 3: Loop Through Each Prompt

Parse the JSON and loop. Each iteration handles one slide: generate the image, then host it.

Step 4: Generate and Host Each Image

Gemini generates the slide from its prompt. The image is then uploaded to a public host that returns the correct Content-Type. Add a short rate-limit delay (the source used 15 seconds) so the image API does not silently throttle you mid-carousel.

Step 5: Carry the URLs Across the Loop With Static Storage

This is the step that took the builder the longest. By default, the URL from slide 1 is gone by the time slide 2 runs, and merge nodes do not cleanly fix it. The fix is workflow static storage: a Code node inside the loop appends each new URL to a global array, and a node outside the loop reads the full array back. This is a reusable pattern for any fan-out-then-fan-in workflow.

Step 6: Collect the URLs and Reset Storage

After the loop, gather all the slide URLs into one array. Reset the static storage immediately, or tomorrow's run inherits today's images.

Step 7: Publish the Carousel in One Call

Send the array of public URLs to the Instagram Graph API as a single carousel post, with the caption.

Step 8: Mark the Row Published

Flag the Data Table row as published so the next run picks up a fresh idea. The feed now advances on its own.

Adapting This for Your Business

The pipeline does not care what the carousel is about. Point the content table at your niche and it produces your posts.

Gotchas and Tips

What This Replaces

Before this pipeline, a consistent carousel feed cost you one of these:

After this pipeline, the production and the posting are both automated, and the only recurring cost is a few cents of API usage per carousel. You are paying for ideas, not for the assembly line that turns them into posts.

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