# Generate and evaluate AI prompts with Gemini and OpenRouter: n8n workflow

> Started by another system calling it, and works across Supabase. It hands the judgement calls to Gemini, Groq and one other.

Source: https://millionrounds.com/workflow/generate-and-evaluate-ai-prompts-with-gemini-and-openrouter (Millionrounds; every figure on the page links to its filing or article)

[Automation library](https://millionrounds.com/workflows) · [Data collection](https://millionrounds.com/workflows?category=Data+collection#library)

# Generate and evaluate AI prompts with Gemini and OpenRouter

Started by another system calling it, and works across Supabase. It hands the judgement calls to Gemini, Groq and one other. 14 steps: a working afternoon to understand properly.

Medium Calls a model: Gemini, Groq

[Download free](https://millionrounds.com/login?next=%2Fapp%2Fworkflow%2Fgenerate-and-evaluate-ai-prompts-with-gemini-and-openrouter)

**14 steps** Medium: a working afternoon

**0** Branches: places the flow splits

**0** Loops or waits

**1** Service it connects to

## The flow

Starts it 2 Model 8 Logic 3 Service 1

The steps in the order they run, from what starts it.

- 1 **Webhook** Webhook *Starts it*
- 2 **Google Gemini Chat Model** Lm Chat Google Gemini *Model*
- 3 **OpenRouter Chat Model** Lm Chat Open Router *Model*
- 4 **Groq Chat Model** Lm Chat Groq *Model*
- 5 **Cohere Chat Model** Lm Chat Cohere *Model*
- 6 **Extract Goal** Code *Logic*
- 7 **Creative Prompt Agent** Agent *Model*
- 8 **Marketing Prompt Agent** Agent *Model*
- 9 **Technical Prompt Agent** Agent *Model*
- 10 **Best Prompt Evaluator** Agent *Model*
- 11 **Merge** Merge *Logic*
- 12 **Respond to Webhook** Respond To Webhook *Starts it*
- 13 **Combine Agent Outputs** Code *Logic*
- 14 **Create a row** Supabase *Service*

## How it's built

- **Starts on:** Another system calling it
- **Steps:** 14
- **Size:** Medium: a working afternoon
- **Connects to:** Supabase
- **Model:** Gemini, Groq, OpenRouter

## Questions

What does it need to run?

An n8n account, plus your own Supabase account, and a key for Gemini and Groq. You connect your own accounts after importing it; none are included.

What starts it?

It starts on another system calling it.

Does it use AI?

Yes. It calls Gemini, Groq and OpenRouter. Model calls are billed by the provider, not by n8n.

How long does it take to set up?

Plan an afternoon. 14 steps is enough that you should read each one before running it.

How do I import it?

Copy the workflow, open a new workflow in n8n and paste. The steps appear on the canvas, ready for your own accounts.

**Before you run it**

Nothing here has been tested by us. It is somebody's working automation, read and described from its own steps. Treat the connections it wants as a list of accounts it will touch, and read the 14 steps before you point it at anything that matters.

## Run it in n8n

- **Create your n8n account** Free to start. n8n is where the workflow runs. [Create an n8n account ↗](https://millionrounds.com/n8n)
- **Download the workflow** Free with a Millionrounds account. [Download free](https://millionrounds.com/login?next=%2Fapp%2Fworkflow%2Fgenerate-and-evaluate-ai-prompts-with-gemini-and-openrouter)
- **Paste it into n8n** Open a new workflow in n8n and paste. Then connect your own accounts.

Stored with the author's traces removed: canvas notes, instance identifiers, saved credential names and any live document they had left behind.

## Connects to

Each opens the other workflows that use it.

[Supabase](https://millionrounds.com/workflows?service=Supabase#library)

## Workflows like it

Also data collection, with the same services where possible, closest in size first.

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