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Test and Improve Your LLM Prompts

Fix the prompts behind your AI features and prove it: a sharper version, a test set with real attacks, and old versus new compared case by case on your models.

Test and Improve Your LLM Prompts agent board

About

Stop guessing whether a prompt change helped. Get a sharper prompt, the cases that prove it, and an engineer's view of the guardrails and model behind it.

What it does

  • Diagnoses a prompt or an agent's instructions and rewrites it, with every change explained
  • Builds a test set from your real failures plus edge cases and attacks such as prompt injection and data leaks
  • Runs old versus new, or several models, on the same cases and compares quality, latency and cost
  • Designs guardrails that screen messages for injections, personal data and policy breaches
  • Helps integrate LLM features into your code and tune model serving with vLLM or TensorRT-LLM

What you need

  • Nothing to start: paste a prompt and say what goes wrong
  • GitHub (optional) to read the code around your prompts and propose changes as a pull request
  • An API key for your model provider (optional) to run the tests on your real models; it is stored as a secret, never in chat or code

How setup works

You get a rewritten prompt and a first test set in the first minutes. It then learns your models, what a failure costs you and where your prompts live, and reruns the tests on your real model.

What stays in your hands

  • It never sends your customer data to a new model or service without your go-ahead
  • Code changes arrive as a pull request you review; it never pushes to your main branch

What you will need

  • GitHub

Coworkers in this template

AI Engineer

Makes your LLM features reliable: sharper prompts tested against real cases, the right model, guardrails and serving that hold up in production.

Apps

Skills · 6

Build an LLM feature

Use when asked to build or integrate an LLM or machine-learning feature into an app, from the model and pipeline to deployment.

Compare models on a task

Use when asked which model to use, or to run the same prompt and data through several models and compare their answers.

Improve a prompt

Use when asked to fix, improve or rewrite a prompt, a system prompt or an agent's instructions.

Run an agent test campaign

Use when asked to test a chatbot or agent automatically, red-team it, or check its guardrails on a batch of messages.

+2 more

Frequently asked questions

How does it prove the new prompt is better?

It builds a test set from your real failures, edge cases and attacks, runs the old and new prompt on every case and grades them against a rubric you agree on, with regressions called out.

Can it test on GPT, Claude or Gemini?

Yes, once you give it an API key for your provider, stored as a secret. It can run the same cases on several models and compare quality, latency and cost per call.

Can it red-team my chatbot for prompt injection?

Yes. Its test sets include injection attempts, requests for internal data and off-policy promises, and it can design a guardrail that blocks, redacts or escalates those messages.

Does it change my code?

Only through a pull request you review, once GitHub is connected. It never pushes to your main branch.

Can it help me serve an open model with vLLM?

Yes. It proposes model, quantization and batch settings for your hardware and traffic, and writes the benchmark script to measure throughput and latency on your GPUs.

How much does it cost to run?

The template is free. Runs use your Rerun credit; calls to your own model provider are billed by that provider on your key.

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