Detect Reddit Problems & Auto-Comment Solutions with Google Gemini & Sheets

| N8N Workflow | AI Reddit Problem Detection & Auto-Solution Commenter 🤖

This n8n workflow automates Reddit community engagement by detecting posts that discuss problems and automatically replying with AI-generated solutions — powered by Google Gemini.

It’s designed for developers, automation creators, and brands who want to provide helpful, automated responses to Reddit users discussing issues in their niche.

How It Works

The workflow starts with a Manual Trigger (When clicking ‘Execute workflow’). Search for a Post: It scans the r/n8n subreddit (or any subreddit you set) for recent posts containing the keyword “Why I stopped using”. Filter Posts (If Node): Filters posts that have 2 or more upvotes and non-empty text, ensuring only quality discussions are analyzed. Edit Fields: Extracts post details such as title, body text, upvotes, creation time, and subreddit ID for AI processing.

AI Agent + Google Gemini Chat Model: The first AI node analyzes the post and decides whether it’s describing a problem or frustration related to AI automation.

Gemini responds with “Yes” or “No.”

Conditional Branch (If1 Node): If “Yes,” the post is confirmed as discussing a problem. The workflow then triggers the second AI Agent.

AI Agent 2 + Gemini: The second AI node uses Gemini to generate a helpful and concise solution addressing the issue mentioned in the Reddit post (for example, offering a fix, suggestion, or new idea).

Merge & Log Data: The AI’s findings (post details + solution) are merged and saved into a connected Google Sheet for tracking community insights.

Comment on Reddit: The workflow automatically posts the AI-generated solution as a comment reply on the original Reddit thread, engaging users directly.

How To Use Import the provided JSON workflow into your n8n dashboard.

Set up the required credentials:

Reddit OAuth2 API – for searching and posting comments.

Google Gemini (PaLM) API – for AI text analysis and solution generation.

Google Sheets API – for logging post data and AI results.

Adjust the subreddit name, search keyword, or prompts to fit your niche.

Click Execute Workflow to run the automation.

Requirements Reddit Developer Account (OAuth2 credentials). Google Gemini (PaLM) API account for AI processing. Google Sheets account for saving analysis results.

How To Customize Change the search keyword (e.g., “help with automation,” “issue with API,” etc.). Modify the AI prompts to tailor the solution style (technical, friendly, educational, etc.). Edit the Google Sheet fields to capture more or fewer details. Enable/disable the comment node if you want to manually approve replies before posting. Adjust the Gemini model name (e.g., models/gemini-2.0-flash) or parameters for faster or more creative responses.