Generate and evaluate AI prompts with Gemini, OpenRouter, Groq, Cohere and Supabase
Ready for 3.0Ready for 3.0. This template uses no nodes that n8n 3.0 removes. No removed nodes, versions or helpers found. Static check, last run 2026-10-19.
Rarely used nodes in this template: @n8n/n8n-nodes-langchain.lmChatCohere
Nodes used (10)
- Webhook
n8n-nodes-base.webhook - Google Gemini Chat Model
@n8n/n8n-nodes-langchain.lmChatGoogleGemini - OpenRouter Chat Model
@n8n/n8n-nodes-langchain.lmChatOpenRouter - Groq Chat Model
@n8n/n8n-nodes-langchain.lmChatGroq - Cohere Chat Model
@n8n/n8n-nodes-langchain.lmChatCohere - Supabase
n8n-nodes-base.supabase - Merge
n8n-nodes-base.merge - Respond to Webhook
n8n-nodes-base.respondToWebhook - AI Agent
@n8n/n8n-nodes-langchain.agent - Code
n8n-nodes-base.code
What it does
Quick overview This workflow receives a goal via webhook, generates three prompt candidates using Google Gemini, OpenRouter, and Groq, has Cohere evaluate and select the best prompt, then returns the result to the caller and stores the goal and winning prompt in Supabase. How it works 1. Receives a POST webhook request containing a JSON body with a goal value. 2. Sends the goal to three parallel prompt-engineering agents backed by Google Gemini, OpenRouter, and Groq to generate creative, marketing, and technical prompt candidates. 3. Combines the three generated prompt candidates into a single structured payload. 4. Uses a Cohere-powered evaluator to compare the candidates and return the best prompt (and a reason) as JSON. 5. Responds to the webhook caller with the evaluator output. 6. Creates a new row in a Supabase prompts table, saving the original goal and the selected best prompt. Setup 1. Add credentials for Google Gemini (PaLM), OpenRouter, Groq, and Cohere so the agents and evaluator can run. 2. Add your Supabase API credentials and ensure a prompts table exists with fields/columns for goal and bestprompt. 3. Copy the production webhook URL and send POST requests with { "goal": "..." } from your client or source app.