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.