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Alternatives

Products that do what Open-source playground to red-team AI agents against public prompts does

Fabraix Playground - Test your prompt injection skills against AI agents

  1. 1AP

    Hey, Jared Palmer (creator of this playground) here. Really excited to ship this. I’ve been building this over the past few weeks to compare LLMs from different providers like OpenAI, Anthropic, Cohere, etc. At Vercel, I manage our Frameworks division (including Next.js, Svelte, and Turbo) and wanted to also dogfood some of the latest features in a slightly larger application. This playground takes a lot of inspiration from https://nat.dev and is built on Tailwind, ui.shadcn.com, and some upcoming Vercel products we’re announcing soon. We’re going to continue adding models to…

    2023 · play.vercel.ai

  2. 2OS

    2023 · chathub.gg

  3. 3OS

    We build runtime security for AI agents. The playground started as an internal tool that we used to test our own guardrails. But we kept finding the same types of vulnerabilities because we think about attacks a certain way. At some point you need people who don't think like you. So we open-sourced it. Each challenge is a live agent with real tools and a published system prompt. Whenever a challenge is over, the full winning conversation transcript and guardrail logs get documented publicly. Building the general-purpose agent itself was probably the most fun part. Getting it to reliably use…

    Mar 2026 · github.com

  4. 4
    Fabraix196

    Find gaps in your AI agents before users do

    May 2026 · fabraix.com

  5. 5

    Create 1,000 AI art images a day for free

    2022

  6. 6

    Iterate on cloud apps in milliseconds, not minutes

    2024

  7. 7IM

    I recently dug up an old project in an attempt to improve on it. It's a code sandbox for playing around with HTMX in the browser, that runs a mock server within the sandbox iframe. The server "framework" is loosely based on Django, so if you're familiar with Django, you'll immediately understand what's going on. I recommend clicking through the examples. Github repo: https://github.com/lassebomh/htmx-playground Probably my favorite part is the lack of HTMX specific code. It's designed to mimic the client and server, but really nothing else. In principle, this means that…

    2024 · lassebomh.github.io

  8. 8
    Clawther378

    Give your OpenClaw agent a real task board

    Mar 2026

  9. 9

    Open-source MCP playground to test and introspect servers

    Nov 2025

  10. 10

    The first public arena for AI agents

    Jun 2026 · arena42.ai

  11. 11

    A new creative coding environment in Framer X

    2019

  12. 12OS

    Kshitij and Rahul here. We're building Playground, an open-source sandbox that lets your non-technical teams prototype directly on production codebases, without bugging you (developers) to spin up and maintain another repo. The repo is here: https://github.com/B1u3B01t/design-playground. We've been working together for six years. Last year we built an AI design agent because we thought designers were the biggest bottleneck. But we were wrong. After talking to teams, we realised designers, PMs, founders and even sales people all wanted to quickly change and explore flows…

    Jul 2026

  13. 13

    All the latest AI video tools in a single place

    2025

  14. 14PF

    Hey everyone, I'm Petr. I'm excited to share LangTale Playground (https://langtale.ai/playground), a first-of-its-kind tool enabling anyone to experiment with OpenAI function calls without coding. Born out of a hackathon project, it's now a part of our broader LangTale platform aimed at tackling common developer challenges with Language Learning Models (LLM). These include prompt integration, testing and debugging, version control, auditing, and usage/cost management. Here's our tech stack: Next.js by Vercel, Tailwind CSS, OpenAI, PlanetScale's Vitess database, and the…

    2023 · langtale.ai

  15. 15FA

    Hello! We just released freeact (https://github.com/gradion-ai/freeact), a lightweight agent library that empowers language models to act as autonomous agents through executable code actions. By enabling agents to express their actions directly in code rather than through constrained formats like JSON, freeact provides a flexible and powerful approach to solving complex, open-ended problems that require dynamic solution paths. * Supports dynamic installation and utilization of Python packages at runtime * Agents learn from feedback and store successful code actions as…

    2025 · github.com

  16. 16

    AI tool that turns your prompts into real video games

    Apr 2026 · parallaxpro.ai

  17. 17

    Get real-world tasks done with autonomous AI agents

    Jun 2026 · arena.ai

  18. 18

    Adversarial agent game where you pitch tokens

    2025

  19. 19PF

    I was frustrated that open ai's playground lacks function calls, so I wrote my own more similar to ChatGpt! Now I can: * use the same models I program against * have access to function calls * can see how much it's costing me Side benefit: I can share my API key with a friend so they can use Gpt3.5 & 4 as open ai took their deposit but still labelled their account as free tier - mistakes happen. Prerequisite: an open ai api key https://github.com/acover288/playgpt Use at your own risk as I blindly installed npm packages.

    2023 · gpt342.s3.us-east-1.amazonaws.com

  20. 20IM

    I built this out of frustration as I lead the development of AI features at Yola.com. Prompt testing should be simple and straightforward. All I wanted was a simple way to test prompts with variables and jinja2 templates across different models, ideally somthing I could open during a call, run few tests, and share results with my team. But every tool I tried hit me with a clunky UI, required login and API keys, or forced a lengthy setup process. And that's not all. Then came the pricing. The last quote I got for one of the tools on the market was $6,000/year for a team of 16 people in a…

    2025 · langfa.st

  21. 21

    Vibe-code your Nothing phone

    Oct 2025

  22. 22OS

    Hi HN, We're a small team building AI tutors out of India, and as you might guess, this means we spend a ton of time writing, testing, and refining prompts for LLMs. When we started out, we were using the OpenAI playground but things became tedious when we wanted to compare responses from different models. We tried a bunch of other playgrounds but found them lacking in some features so we built our own. Quick Links: Github: https://github.com/supernova-app/ai-playground Hosted demo: http://playground.getsupernova.ai Demo video:…

    2025 · playground.getsupernova.ai

  23. 23

    Simple, fast way to find and try any MCP server. No setup.

    Feb 2026

  24. 24

    Save 80% on AI Subscriptions and prompt up to 4 models!

    2025

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