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AI · alternatives · 2026

24 alternatives to AgentShield

Your agent runs. You hope. We know — before execution.

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 2 we have checked on their own sites, 2 of them free or with a free tier.

  1. 1

    Your AI agent hits an infinite loop and racks up $2000 in API charges overnight. This happens weekly to AI developers. AgentGuard monitors API calls in real-time and automatically kills your process when it hits your budget limit. How it works: Add 2 lines to any AI project: const agentGuard = require('agent-guard'); await agentGuard.init({ limit: 50 }); // $50 budget // Your existing code runs unchanged const response = await openai.chat.completions.create({...}); // AgentGuard tracks costs automatically When your code hits $50 in API costs, AgentGuard stops…

    2025 · github.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
    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 →

  4. 4
    Bullet▲240

    Hi HN, excited to be sharing this with you guys today. TL;DR: Bullet is a fast coding agent. At our company, we were burning hours waiting on agent runs. The models weren’t the problem. The agent loops around them were slow (unnecessary planning, oversized context, repeated searches, and serial tool calls). So we built Bullet as a passion project, the goal being to help you iterate faster, without giving up quality: - It automatically selects the model and reasoning level for each prompt. - It runs independent searches, reads, and commands in parallel. - It uses targeted code search instead…

    Aug 2026 · codewithbullet.com · its alternatives →

  5. 5

    Scan AI agent Skills for risks before you install them

    17d ago · agentguard-sigma-five.vercel.app · its alternatives →

  6. 6
    Fabraix▲196

    We 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 →

  7. 7

    Your site scores X/100 for AI agents with next steps

    May 2026 · indexedai.tech · its alternatives →

  8. 8

    Security-scored directory for AI skills and agent tools

    Feb 2026 · skillshield.io · its alternatives →

  9. 9

    Build AI Agents. Run Them Anywhere.

    Feb 2026 · crewclaw.com · its alternatives →

  10. 10

    The security layer for AI agents

    Mar 2026 · earlycore.dev · its alternatives →

  11. 11

    Prompt injection detection API for AI agents

    May 2026 · agentshield.pro · its alternatives →

  12. 12

    Hey HN, AI agents are all the buzz right now, but how many of them are accessing your website today? That's what we built AgentShield to answer. Most of our users didn't know they had agent traffic until seeing them in our dashboard. You can see traffic broken down by humans, bots, and AI agents. Installation can be as simple as a JS pixel, and it's free. We're currently building out the paid component that will let you block specific agents or types of traffic. Feedback welcome: What else would you want to know about AI agents visiting your site?

    2025 · kya.vouched.id · its alternatives →

  13. 13

    Hey, I'm Gong Chao, currently working at Zai. Last weekend after playing football and heading home, an idea suddenly popped into my head. I got the urge to build it and spent the whole weekend hacking it out — *AgentShield* . Nowadays everyone's using Cowork, Claude Code, or various AI agents to manipulate files and write code. It's awesome, but sometimes AI goes "crazy" and messes up your files, making it impossible to revert to the original state (don't ask me how I know... ). For code, you have Git, but that requires commits, and it's not friendly for large files. AgentShield puts a…

    Jan 2026 · github.com · its alternatives →

  14. 14

    Project AI agents from unsafe actions before they execute.

    Aug 2026 · agentfirewall.launchreadyal.com · its alternatives →

  15. 15AA

    I'm a solo dev in Taiwan. I built 4 AI agents that handle content, sales leads, security scanning, and ops for my tech agency — all on Gemini 2.5 Flash free tier (1,500 req&#x2F;day). I use ~105. Monthly LLM cost: $0. Architecture: 4 agents on OpenClaw (open source), running on WSL2 at home with 25 systemd timers. What they do every day: - Generate 8 social posts across platforms (quality-gated: generate → self-review → rewrite if score < 7&#x2F;10) - Engage with community posts and auto-reply to comments (context-aware, max 2 rounds) - Research via RSS + HN API + Jina Reader → feed…

    Mar 2026 · its alternatives →

  16. 16AR
  17. 17

    AI agents now have impressive reasoning capabilities. This raises an important question: how dangerous are these AI agents at identifying & exploiting web vulnerabilities? We created CVE-bench to find out (I'm one contributor of 16). To our knowledge CVE-bench is the first benchmark using real-world web vulnerabilities to evaluate AI agents' cyberattack capabilities. We included 40 CVEs from NIST's database, focusing on critical-severity vulnerability (CVSS > 9.0). To properly evaluate agents’ attacks, we built isolated environments with containerization and identified 8 common attack…

    2025 · github.com · its alternatives →

  18. 18
    Runwallfree tier▲9

    A Runtime security layer that lets AI agents execute safely

    Jul 2026 · runwall.vercel.app · its alternatives →

  19. 19

    Hi HN, I’m a solo developer and built AgentWatch to solve a problem I kept running into while building AI agents: preventing runaway loops and unexpected LLM spend before requests reach the model. AgentWatch sits in front of OpenAI, Anthropic, Gemini, Bedrock, Azure OpenAI, Groq, and others to enforce budgets and runtime policies. I’d really appreciate your feedback. If you’re building AI agents, does this solve a problem you’ve experienced? I’d also love to hear what you’d improve or challenge.

    Jun 2026 · agent-watch.dev · its alternatives →

  20. 20

    Security firewall for AI agents. Cloudflare for MCP.

    Feb 2026 · agent-wall.github.io · its alternatives →

  21. 21

    We build the agents so your team doesn't have to.

    Jun 2026 · rapidclaw.dev · its alternatives →

  22. 22

    Find every hidden agent. Fix what's exposed.

    Mar 2026 · agentshield-ai.com · its alternatives →

  23. 23

    Find out if AI will replace your job — in 60 seconds.

    Jun 2026 · careerjanus.com · its alternatives →

  24. 24

    Love OpenClaw? Now ship it to production. Built in Rust.

    Feb 2026 · 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 →