Automate AI Summaries for WordPress with n8n, OpenAI & Slack

What this workflow does

This workflow watches for new or updated posts on WordPress.

It reads the full post content and makes a short summary using AI.

The summary is added to the top of the post in HTML format.

Details of processed posts are saved in Google Sheets.

A message is sent to Slack to inform the team about new summaries.

Who should use this workflow

This is useful for people managing blogs who spend too much time writing post summaries.

It helps avoid missing or duplicate summaries and saves several hours weekly.

No need to install heavy WordPress plugins that slow down the website.

Tools and services used

• n8n automation platform: Runs the workflow.
• WordPress API: Reads and updates posts.
• OpenAI GPT-4o-mini model: Creates human-like summaries.
• Google Sheets: Keeps record of processed posts.
• Slack: Sends notification messages.

Inputs, Processing Steps, and Output

Inputs

• New or updated WordPress posts via API or webhook.
• Google Sheets data to check processed posts.

Processing Steps

• Fetch posts from WordPress.
• Loop through each post one at a time.
• Check Google Sheets if post is already summarized.
• Convert post HTML content to Markdown.
• Use AI to classify if summary exists already.
• If no summary, generate summary using OpenAI GPT-4o-mini with custom prompt.
• Update WordPress post by adding summary block at the top.
• Log the summary details to Google Sheets.
• Notify Slack channel about the update.

Output

• WordPress posts enriched with AI-generated summaries.
• Updated Google Sheets with logged post summaries.
• Slack notifications for team awareness.

Beginner step-by-step: How to use this workflow in n8n

Step 1: Import the workflow

1. Download the workflow file using the Download button on this page.
2. Open n8n editor and use “Import from File” to load the workflow.

Step 2: Configure credentials and settings

1. Add your WordPress API credentials and test them.
2. Enter your OpenAI API key for GPT-4o-mini model access.
3. Set up Google Sheets credentials and check that the correct sheet and columns are used.
4. Configure Slack OAuth2 credentials and select the correct channel for notifications.
5. Update any IDs, emails, or table names if needed to match your setup.

Step 3: Test the workflow

1. Run a manual test trigger or wait for the scheduled trigger if used.
2. Confirm the workflow fetches the posts and adds AI summaries correctly.
3. Check Google Sheets logs and Slack messages for expected output.

Step 4: Activate for production

1. Enable the Schedule Trigger or Webhook node.
2. Ensure all nodes show as active and will run on schedule or webhook call.
3. Monitor the workflow executions and adjust trigger intervals if needed.

This is all you must do to start automating intelligent summaries in your WordPress blog with n8n.

For full control or privacy, use self-host n8n to run this workflow on your own server.

Customization ideas

• Change the AI system prompt in the OpenAI node to fit other blog topics.
• Adjust the HTML style in the summary block to match your website design.
• Add more columns like post author or category in Google Sheets and Slack messages.
• Switch between Schedule Trigger or Webhook node depending on need for real-time updates.
• Modify loop batch sizes if lots of posts require processing.

Troubleshooting

• Trigger node does not activate: Make sure the Schedule or Webhook node is enabled and authentication is correct.
• WordPress API errors 401 or 403: Verify your API keys and user permissions.
• Google Sheets lookup fails: Check column names and sharing permissions carefully.
• OpenAI node errors or empty replies: Check API key, monitor rate limits, and use proper prompts.
• Slack notifications missing: Confirm channel ID and app permissions.
• Excerpt overwritten incorrectly: Review the WordPress update payload and test with a sample post.

Pre-Production Checklist

• Test trigger node activation with manual or scheduled runs.
• Confirm WordPress API read and write permissions.
• Ensure Google Sheets lookup and append work properly.
• Verify OpenAI connection and correct prompt usage.
• Send test Slack message to confirm notifications.
• Clear Google Sheets logs to avoid duplicates before running bulk.
• Run tests on few posts before processing many.

Deployment Guide

Pick your trigger method: scheduled or real-time webhook.

Activate the workflow in n8n and make sure credentials are correct.

Watch execution logs to catch issues early and tune frequency or batch sizes.

Use Slack and Google Sheets for easy monitoring of progress and audit.

Update the prompt over time to keep summaries relevant as content changes.

Summary of benefits and results

✓ Saves around 4 hours each week by automating summaries.
✓ Avoids manual errors like missing or duplicate summaries.
✓ Keeps post excerpts intact for SEO.
✓ Provides easy audit trail with Google Sheets logging.
✓ Notifies the team via Slack about new summaries.
✓ Works without adding extra heavy plugins to WordPress.