Create & Publish Instagram Carousel Posts with GPT-4.1-mini, Imgur & Graph API

Create & Publish Instagram Carousel Posts with GPT-4.1-mini, Imgur & Graph API

Version: 2.0.0 n8n Version: 1.88.0+ Author: Unknown License: MIT

Description

An intelligent and modular workflow that automatically generates, manages, and publishes Instagram carousel posts, using AI for both content and images. It includes semantic memory to ensure uniqueness across posts and a scalable architecture for brand growth.

Key Features

• 🤖 Advanced AI Carousel Content: Generates unique multi-slide post content—titles, captions, hashtags, and strategic CTAs for each card in the carousel.
• 🎨 Automated Image Generation: Creates high-quality visuals for every slide using OpenAI's DALL·E API.
• 🧠 Semantic Memory Search: Checks each theme against a local vector database using OpenAI Embeddings to avoid content repetition.
• 📊 Publication Database: Logs all generated carousel posts into Google Sheets for tracking, analytics, and audits.
• 📱 Instagram Direct Publishing: Publishes carousel media and captions automatically through the Instagram Graph API.
• 🗓️ Scheduled & Manual Runs: Trigger manually or schedule every 12 hours.
• 🔐 Secure Credential Management: Uses n8n credential fields—no hardcoded API keys or tokens.
• 🚀 Flexible Prompting System: Dynamically adapts style templates for different brands and industries.

Use Cases

1. E‑commerce Launches: Showcase product features across multiple slides with tailored benefits and CTAs.
2. Fitness & Wellness Tips: Educate followers with step-by-step workouts or nutrition advice in a carousel format.
3. Educational Infographics: Present multi-part tutorials, stats, or course highlights.
4. SaaS Feature Demos: Demonstrate software workflows or new features slide by slide.
5. Event Announcements: Build excitement for webinars, conferences, or local meetups.

Customization Examples

• Retail/E‑commerce: Adjust the Theme Generator Code Node to include product category, price point, and seasonal focus as vector inputs.
• Health & Fitness: Tweak the AI Prompt Templates to match your brand voice—e.g., friendly coach tone with bullet‑pointed workout steps.
• Education/Training: Modify the Semantic Memory Embeddings Node thresholds to deepen topic variety across tutorial series.
• Tech/SaaS: Customize the Image Hosting HTTP Request Node to use your company’s CDN instead of Imgur by swapping the endpoint and credential field.

Workflow Overview

1. Theme Generation (Generate Theme Code Node)

• Combines random vectors (topic starter + focus + benefit) to create unique carousel themes.

2. Content Creation (AI Agent Code Node)

• Sends themed prompts to OpenAI, generating slide-by-slide titles, captions, and CTAs in structured JSON.

3. Semantic Memory Check (OpenAI Embeddings Node)

• Runs embeddings against past themes stored in a Postgres vector database (pgvector) to ensure novelty.
• If similarity > threshold, regenerates theme.

4. JSON Validation (Parse & Validate Code Node)

• Parses AI response, validates JSON schema, and handles errors gracefully to prevent workflow failures.

5. Content Storage (Google Sheets Node)

• Writes carousel metadata (titles, captions, hashtags, slide count, scheduled date) to a Google Sheets spreadsheet.

6. Image Generation (DALL·E Image Generation Node)

• Generates one graphic per slide at 1024×1024 resolution.

7. Image Hosting (Imgur Upload HTTP Request Node)

• Uses an HTTP Request node with Imgur credential field to upload each image and retrieve public URLs.

8. Instagram Publishing (Instagram Graph API Nodes)

• Create Media Containers: Sends batch media creation request.
• Publish Carousel: Publishes the carousel using the list of container IDs and caption.

9. Scheduling & Triggers

• Manual Trigger: For testing and one‑off posts.
• Cron Trigger: Scheduled trigger every 12 hours (configurable).

Security

All sensitive values (OpenAI API key, Imgur Client ID/Secret, Instagram Access Token, Google Sheets OAuth2) must be stored in n8n’s Credentials panel. Do not hardcode keys or tokens in HTTP Request or Code nodes. Instead, reference credential fields:

• In HTTP Request nodes: select the corresponding credential under Authentication.
• In Code nodes: access this.getCredentials('openAI'), this.getCredentials('imgur'), etc.

Instructions

1. Import the Workflow: In n8n, go to Workflows > Import from File and upload the JSON.

2. Configure Credentials:

   • OpenAI API – set up in Credentials > OpenAI API.
   • Google Sheets OAuth2 – set up in Credentials > Google Sheets OAuth2.
   • Imgur – set up in Credentials > Imgur.
   • Instagram Graph API – set up in Credentials > Instagram Graph API.

3. Set Placeholders:

   • Google Sheets Document ID
   • Instagram User ID

4. Customize Prompts & Vectors: Tweak Code node inputs and prompt templates as needed.

5. Test & Activate: Run a manual trigger, verify outputs, then enable the cron schedule.

Tags

Social Media Instagram Carousel AI Content Generation OpenAI n8n Marketing Automation Vector Search Content Scheduling

Technical Notes

• Uses pgvector in Postgres for efficient semantic similarity.
• Supports extensible platforms—duplicate the publishing steps to add LinkedIn or Facebook.
• Error handling ensures invalid JSON never reaches the publishing nodes.

License

This workflow is released under the MIT License.