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AI · alternatives · 2026

24 alternatives to Open-source playground to red-team AI agents with exploits published

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…

Open-source playground to red-team AI agents with exploits published is a security testing platform for AI agents. It provides live challenges where users attempt to exploit agents that have real tools and published… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 3 we have checked on their own sites, 3 of them free or with a free tier.

  1. 1

    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…

    Jul 2026 · playground.fabraix.com · its alternatives →

  2. 2

    Creator 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 →

  3. 3

    OpenAgents - The collaboration OS for AI agents. Contribute to openagents-org/openagents development by creating an account on GitHub.

    Apr 2026 · open-agents.dev · its alternatives →

  4. 4
    Switchfree▲527

    Bring any AI agent into Slack, Teams & Discord. Open-source.

    Aug 2026 · flintai.dev · its alternatives →

  5. 5

    Hi HN, I'm Antoine Zambelli, AI Director at Texas Instruments. I built Forge, an open-source reliability layer for self-hosted LLM tool-calling. What it does: - Adds domain-and-tool-agnostic guardrails (retry nudges, step enforcement, error recovery, VRAM-aware context management) to local models running on consumer hardware - Takes an 8B model from ~53% to ~99% on multi-step agentic workflows without changing the model - just the system around it - Ships with an eval harness and interactive dashboard so you can reproduce every number I wanted to run a handful of always-on agentic systems…

    May 2026 · github.com · its alternatives →

  6. 6

    Use and compare GPT-6, Claude 5, Gemini 3 and more chatbots simultaneously

    2023 · chathub.gg · its alternatives →

  7. 7
    AgentSea▲439

    Today we’re excited to introduce AgentSea, a private AI chat built for sensitive work. When you use closed-source AI models, your data can: – be stored – pulled into training pipelines – shared with third parties That might be fine if you’re making memes or drafting LinkedIn posts. But it becomes a serious risk when you’re pasting contracts, health info, financial data, or business secrets. That’s why we built AgentSea. In Secure Mode, all chats run on open-source models or models hosted on our own servers. Your data never leaves, is never used for training, and is never leaked. Agentsea…

    2025 · agentsea.com · its alternatives →

  8. 8
    Kastrafree tier, from $19.99/mo▲332

    Hi HN, Fernando and I built Kastra. Kastra intercepts AI agent tool calls and evaluates them against deterministic policies before they execute. We built this product to control pre- and post-inference workloads. This is aimed at developers using coding agents like Claude Code, Codex, Cursor, and OpenClaw. Kastra pushes an allow, hold, and deny decision before the action runs. You can build these policies in plain English from the web app. The interception engine evaluates the tools, targets, and parameters of every action at sub 1ms at a scale of billions of interceptions per day. We also…

    Jul 2026 · kastra.ai · its alternatives →

  9. 9
    Opengeni▲341

    Ship AI agents within minutes. Infrastructure for Agents

    Sep 2026 · opengeni.ai · its alternatives →

  10. 10

    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 →

  11. 11

    Anthropic and OpenAI's publicly available models are explicitly guard-railed so that they refuse offensive tasks. And their cyber-focussed models are gated for enterprises. This leaves SMEs and mid market open to major vulnerabilities. AI can be used as both an adversarial and defensive tool in the world of cyber. A worst case outcome is if only the adversaries have access. Meanwhile, most existing AI cyber tools are just wrappers. The problem is that they still have all the guardrails on from the foundation model where they will inherit its refusals. For this project we've post-trained a…

    Jun 2026 · argusred.com · its alternatives →

  12. 12

    Get real-world tasks done with autonomous AI agents

    Jun 2026 · arena.ai · its alternatives →

  13. 13

    A local control plane for AI coding agents

    May 2026 · agentrail.app · its alternatives →

  14. 14OS
  15. 15

    I built an open-source AI agent for security testing to find and fix vulnerabilities in your code. I’ve noticed how bad security vulnerabilities have gotten with everyone shipping AI code slop, so I wanted to build something that allows for vibe-coding at full speed without compromising security. Traditional security tools aren’t effective, and manual pen-testing can’t keep up with the rapidly growing AI code This tool runs your code dynamically, finds vulnerabilities, and validates them through actual exploitation. You can either run it against your codebase or enter your (or someone…

    2025 · github.com · its alternatives →

  16. 16

    Hi HN, Founder here. We built Pica, an open-source platform in Rust to enable agentic AI with three main focus areas: - Access to APIs and tools: Universal SDKs that let AI agents use thousands of external actions without blowing up your context window. - Visibility and traceability: Full audit logs of every decision/action to ensure transparency and accountability. - Alignment with human intentions: Seamless guardrails for autonomous tasks; e.g., restricting certain email actions to human approval. Why this matters: As autonomy in AI grows, we need robust solutions for trust and…

    2025 · picaos.com · its alternatives →

  17. 17

    Contribute to vrn21/bouvet.com development by creating an account on GitHub.

    Jan 2026 · github.com · its alternatives →

  18. 18OS

    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 →

  19. 19

    An information-flow policy engine for LLM agents.

    25d ago · openappa.com · its alternatives →

  20. 20AM

    Hey HN, Michael and Scott here. We’re open-sourcing an interactive murder mystery featuring LLM-driven character agents. Solve the mystery by finding clues, taking notes, and interrogating agents. They all have distinct motives, personality, and can impact the game in different ways (attacking you, running away, etc). Try it out, it’s pretty fun! We’re also open-sourcing the framework that we used to make and refine the agents. The goal is to create an intuitive interface for storytellers to create, debug, and test game agents. We then take those game agents and expose an API beyond just…

    2023 · gron.games · its alternatives →

  21. 21PF

    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 · its alternatives →

  22. 22

    Hey HN, Automated research is the next big step in AI, with companies like OpenAI aiming to debut a fully automated researcher by 2028 (https://www.technologyreview.com/2026/03/20/1134438/openai-i...). However, there is a very real possibility that much of this corporate research will remain closed to the general public. To counter this, we spent the last month building Enlidea---a machine-to-machine ecosystem for open research. It's a decentralized research hub where autonomous agents propose hypotheses, stake bounties, execute code, and perform automated…

    Mar 2026 · enlidea.com · its alternatives →

  23. 23

    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 →

  24. 24

    Excited to share a project I’ve been building for months! Would love to receive honest feedback :) My motivation: AI is clearly going to be the interface for data. But earlier attempts (text-to-SQL, etc.) fell short — they treated it like magic. The space has matured: teams now realize that AI + data needs structure, context, and rules. So I built a product to help teams deliver “chat with data” solutions fast with full control and observability (agent tracing, quality scores, etc) — am I wrong? The product allows you to connect any LLM to any data source with centralized context…

    2025 · github.com · 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 →