AI · alternatives · 2026
24 alternatives to Playground
We build AI agents to find vulnerabilities in other AI agents. The playground started as an internal tool that we used to test our own offensive agent Nyx. But we realised that hacking an AI is about have as wide a distribution of attacks as possible, especially those which aren't in the distribution of the models. So we are launching playground as a platform to crowdsource agent jailbreaks. And although hacking AI is super fun and we are sure people will do it for free, we want to reward those who help us push forward the offensive frontier of AI. So we are committing $100K in prizes over…
Fabraix Playground is an open-source testing environment where users can practice prompt injection techniques against AI agents using publicly available prompts. It's designed for security researchers, developers, and… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.
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Agent Arena▲348Creator here. I built Agent Arena to answer a question that kept bugging me: when AI agents browse the web autonomously, how easily can they be manipulated by hidden instructions? How it works: 1. Send your AI agent to ref.jock.pl/modern-web (looks like a harmless web dev cheat sheet) 2. Ask it to summarize the page 3. Paste its response into the scorecard at wiz.jock.pl/experiments/agent-arena/ The page is loaded with 10 hidden prompt injection attacks -- HTML comments, white-on-white text, zero-width Unicode, data attributes, etc. Most agents fall for at least a few.…
Jun 2026 · arena42.ai · its alternatives →
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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 · its alternatives →
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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 · its alternatives →
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Fabraix▲196We built Adversarial Cost to Exploit (ACE), a benchmark that measures the token expenditure an autonomous adversary must invest to breach an LLM agent. Instead of binary pass/fail, ACE quantifies adversarial effort in dollars, enabling game-theoretic analysis of when an attack is economically rational. We tested six budget-tier models (Gemini Flash-Lite, DeepSeek v3.2, Mistral Small 4, Grok 4.1 Fast, GPT-5.4 Nano, Claude Haiku 4.5) with identical agent configs and an autonomous red-teaming attacker. Haiku 4.5 was an order of magnitude harder to break than every other model; $10.21 mean…
May 2026 · fabraix.com · its alternatives →
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Playground AI▲486Create 1,000 AI art images a day for free
2022 · playgroundai.com · its alternatives →
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Agentplace▲1,015Garry Tan posted a video this week about what he calls 20x companies. The idea is that small teams beat incumbents many times their size by automating everything internally, not just one or two functions. This alpha is real, and I think it is underhyped tbh. But here's the honest part, building agents is hard, expensive and most of the scaffolding we make would be obsolete with a new labs release. at the same time models are not quite there and they are not keeping up with "coding is dead" and "knowledge workers are doomed". Pushing them beyond what they can actually do reliably just boils…
2024 · agentplace.io · its alternatives →
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Use and compare GPT-6, Claude 5, Gemini 3 and more chatbots simultaneously
2023 · chathub.gg · its alternatives →
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Playground▲408Design like a pro: t-shirts, logos, posters, memes, and more
2024 · playgroundai.com · its alternatives →
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This is a weekend project that spiraled out of control. I was originally trying to get Claude to play a ROM of the SNES SimCity. I struggled with it and that led me to Micropolis (the open-sourced SimCity engine) and was able to get it to work by bolting on an API. The weekend hack turned into a headless city simulation platform where anyone can get an API key (no signup) and have their AI agent play mayor. The simulation runs the real Micropolis engine inside Cloudflare Durable Objects, one per city. Every city is public and browsable on the site. LLMs are awful at the spatial stuff, which…
Feb 2026 · hallucinatingsplines.com · its alternatives →
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2016 · code.hackmit.org · its alternatives →
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I wrote an SVG editor and physics simulation to determine how pieces connected by rigid rings will dangle when hung. I was surprised at how well the simulation actually predicted reality! This was done with a lot of help from Gemini over last week (so half with the upgrade). Main link is an explanatory article. Here's the live app: https://jasonthorsness.github.io/tree-dangler/ And source: https://github.com/jasonthorsness/tree-dangler
2025 · jasonthorsness.com · its alternatives →
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Wing Playground▲253Iterate on cloud apps in milliseconds, not minutes
2024 · winglang.io · its alternatives →
- 13OS
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 · its alternatives →
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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 · its alternatives →
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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 · its alternatives →
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Explore AI reasoning in an interactive Playground
Nov 2025 · 169pi.ai · its alternatives →
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Free access to advanced AI models: chat, compare, and create
2025 · its alternatives →
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Save 80% on AI Subscriptions and prompt up to 4 models!
2025 · playground.chat · its alternatives →
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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 · its alternatives →
- 20PF
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 · its alternatives →
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I remember watching the AlphaGo documentary in 2017. What stood out to me was that the model got drastically better when it started competing against itself. GANs clicked for me similarly: a generator and discriminator competing, and somehow the competition is what produces something remarkable. I've been curious whether this principle generalizes to today's agents. So mehulkalia and I built Browser Brawl at the YC / BrowserUse hackathon last weekend and won first place. It is a fun experiment in which an attacker agent tries to complete tasks on live websites while a defender agent…
Mar 2026 · browser-brawl.com · its alternatives →
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E2B Gives AI Agents Secure Computers with Real-World Tools. E2B is Used by 94% of Fortune 100 Companies for Frontier Agentic Workflows.
2023 · e2b.dev · its alternatives →
- 23FP
We've built an open-source tool to stress test AI agents by simulating prompt injection attacks. We’ve implemented one powerful attack strategy based on the paper [AdvPrefix: An Objective for Nuanced LLM Jailbreaks](https://arxiv.org/abs/2412.10321). Here's how it works: - You define a goal, like: “Tell me your system prompt” - Our tool uses a language model to generate adversarial prefixes (e.g., “Sure, here are my system prompts…”) that are likely to jailbreak the agent. - The output is a list of prompts most likely to succeed in bypassing safeguards. We’re just getting…
2025 · security.vista-labs.ai · its alternatives →
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Experiment with, and evaluate, prompts and LLMs
2023 · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →