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Dev tools · alternatives · 2026

24 alternatives to I Built a Sandbox for Agents

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

I Built a Sandbox for Agents is an open-source project that provides a controlled environment for testing and running AI agents. Available on GitHub, it lets developers safely experiment with agent behavior in isolated… 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

    Test your AI apps with thousands of digital humans

    2025 · agentsimulate.com · its alternatives →

  2. 2

    Build production agents with harness and sandbox

    Apr 2026 · openai.com · its alternatives →

  3. 3

    Open Source agent Sandboxes. Contribute to mihirahuja1/agentnestOSS development by creating an account on GitHub.

    Jul 2026 · github.com · its alternatives →

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    hi guys. been working on something i think is fundamentally missing in today's workflow with ai agents. vcs. i find myself struggling with questions that agents can't answer like "why did you do it?", "when did u delete this folder? why?", etc. or trying to /rewind (after a /compact...) or basically `bisect` to find when and why something was done by the agent in the current / previous session. just like git did for code, i think we are the same core capabilities with ai agents so... i developed an open source solution for that (currently supporting claude code) would love to…

    May 2026 · github.com · its alternatives →

  5. 5

    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 →

  6. 6
    Agent Sandboxfree tier, from $0.00025/mo▲97

    Your agent's personal remote computer and drive

    Feb 2026 · agentsandbox.co · its alternatives →

  7. 7

    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 →

  8. 8

    Hi HN! We just launched Verdent, an AI coding agent that actually plans before it codes, tests its own work, and delivers production-ready results without you having to clean up after it. tl;dr Check out the website [1] and read the story [2] - The problem: Current AI tools dump code and leave you to debug. You ask for "build a login endpoint" and get a passwordless JWT mess that doesn't fit your project. We've talked to hundreds of engineers who are frustrated with having to micromanage AI output. - What we built: Verdent works more like a senior engineer. It asks clarifying questions…

    2025 · verdent.ai · its alternatives →

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    Tilde started from a simple observation: AI agents are only as useful as the environment they can work in. Giving an agent a prompt is easy. Giving it the right files, credentials, tools, context, and execution environment, safely and repeatably, is much harder. Over the past year, we learned a lot

    May 2026 · tilde.run · its alternatives →

  10. 10

    We’ve been working with automating coding agents in sandboxes as of late. It’s bewildering how poorly standardized and difficult to use each agent varies between each other. We open-sourced the Sandbox Agent SDK based on tools we built internally to solve 3 problems: 1. Universal agent API: interact with any coding agent using the same API 2. Running agents inside the sandbox: Agent Sandbox provides a Rust binary that serves the universal agent API over HTTP, instead of having to futz with undocumented interfaces 3. Universal session schema: persisting sessions is always problematic, since…

    Jan 2026 · github.com · its alternatives →

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    Boxes.devfree tier, from $19/mo▲112

    Hi HN, we’re Nick and Drew, and we’re building boxes.dev – the first cloud-only agentic dev environment (ADE) that gives every Codex and Claude Code agent its own cloud computer. We’re two engineers who previously built Gem (co-founder/CTO and first hire), and we spent the last year coding almost exclusively using Codex and Claude Code. It’s been a huge change to how we code, and it’s been exhilarating seeing the models keep getting better – but we eventually realized that developing on localhost was holding us back: - Git worktrees are clunky to set up and use for parallelizing work -…

    Jun 2026 · boxes.dev · its alternatives →

  12. 12
    Buda▲197

    Run a full AI agent team in the cloud — no hardware, no setup. Persistent memory, browser automation, parallel agents. The OpenClaw alternative built for teams. Start free.

    May 2026 · buda.im · its alternatives →

  13. 13
    OpenBox▲171

    See, verify, and govern every agent action.

    Apr 2026 · openbox.ai · its alternatives →

  14. 14

    Instant, hardware Isolated Sandboxes for AI agents

    Jul 2026 · createos.sh · its alternatives →

  15. 15

    Get real-world tasks done with autonomous AI agents

    Jun 2026 · arena.ai · its alternatives →

  16. 16MO

    Hey everyone, We're excited to introduce MarinaBox, an open-source toolkit for creating isolated desktop/browser sandboxes tailored for AI agents. Over the past few months, we've worked on various projects involving: 1. AI agents interacting with computers (think Claude computer-use scenarios). 2. Browser automation for AI agents using tools like Playwright and Selenium. 3. Applications that need a live-session view to monitor AI agents' actions, with the ability for human-in-the-loop intervention. What we learned: All these scenarios share a common need for robust infrastructure. So,…

    2024 · github.com · its alternatives →

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    Just watched this video by ThePrimeagen (https://www.youtube.com/watch?v=efwDZw7l2Nk) about attackers jailbreaking Claude to run cyber attacks. The core issue: AI agents need isolation. We built ERA to fix this – local microVM-based sandboxing for AI-generated code with hardware-level security. Think containers, but safer. Such attacks wouldn't touch your host if running in ERA. GitHub: https://github.com/BinSquare/ERA Quick start: https://github.com/BinSquare/ERA/tree/main/era-agent/tutoria... Would love your…

    Nov 2025 · github.com · its alternatives →

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    Instant recall for coding agents. Search the history already on your machine. Git blame, but for agent sessions.

    Apr 2026 · ctx.rs · its alternatives →

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    I'm Josh, founder of Synth. We've been working on coding agent optimization with method like GEPA and MIPRO (the latter of which, I helped to originally develop), agent evaluation via methods like RLMs, and large scale deployment for training and inference. We've also worked on patterns for memory, processing live context, and managing agent actions, combining it all in a single stack called Horizons. With the release of OpenAI's Frontier and the consumer excitement around OpenClaw, we think the timing is right to release a v0. It integrates with our sdk for evaluation and optimization but…

    Feb 2026 · github.com · 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 →

  21. 21

    Hi HN, I'm Jonathan. My co-founder, Thomas, and I started building Mistle in Feb. We saw larger tech companies like Ramp (Inspect) and Stripe (Minions) build this internally and thought an open source version should exist. We made a few very intentional decisions when working on this: 1. Credentials are kept out of the sandbox. Authorized access goes through a proxy, so agents do not directly receive credentials. 2. The harness is not our problem. We're not going to tackle things like memory, self-learning. 3. No magic. Configurations are explicit. You can bring your own keys for models,…

    May 2026 · github.com · its alternatives →

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    Run Claude Agent SDK in sandboxed environments

    Jan 2026 · github.com · its alternatives →

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    Run a coding agent in a sandboxed environment. Contribute to sin-ack/agent-run development by creating an account on GitHub.

    Jul 2026 · github.com · its alternatives →

  24. 24

    Hi HN, This is a project I've been working on since the beginning of 2025 full time, without funding. Coding agents have fundamentally changed the way we write software. When you let an agent write code, pull dependencies, and run scripts, you are delegating trust while still keeping the responsibility. You shouldn't have to choose between moving fast with agents and maintaining basic control over your host machine. Normally, we just inspect the final result, treating the app like a black box. Most security tools only sandbox the app runtime and ignore the build phase. CapaKit is my attempt…

    Jun 2026 · capakit.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 →