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Alternatives

Products that do what Prompt-injection firewall for AI agents does

Block malicious web content before it reaches your AI.

  1. 1SA

    Alright so if you run a self-hosted blog, you've probably noticed AI companies scraping it for training data. And not just a little (RIP to your server bill). There isn't much you can do about it without cloudflare. These companies ignore robots.txt, and you're competing with teams with more resources than you. It's you vs the MJs of programming, you're not going to win. But there is a solution. Now I'm not going to say it's a great solution...but a solution is a solution. If your website contains content that will trigger their scraper's safeguards, it will get dropped from their data…

    Dec 2025 · github.com

  2. 2

    Block prompt inject & cut token costs for AI browser agents

    Jun 2026 · github.com

  3. 3OS

    Hi HN, Matvey, Ildar, Joey, and Dominik here. If you're building LLM agents that use tools, you're probably worried about prompt injection attacks that can hijack those tools. We were too, and found that solutions like prompt-based filtering or secondary "guard" LLMs can be unreliable. Our thesis is that agent security should be handled at the network level between the agent and the LLM, just like a traditional web application firewall. So we built Archestra Platform: an open-source gateway that acts as a secure proxy for your AI agents. It's designed to be a deterministic firewall against…

    Oct 2025 · archestra.ai

  4. 4

    The AI-Powered Antivirus for AI Agents

    May 2026 · clawsecure.ai

  5. 5

    The firewall for AI prompts. Drop-in security for LLM apps.

    Dec 2025

  6. 6IB

    Hi HN, I’m the creator of Cordum. I’ve been working in DevOps and infrastructure for years (currently in the fintech/security space), and as I started playing with AI agents, I noticed a scary pattern. Most "safety" mechanisms rely on system prompts ("Please don't do X") or flimsy Python logic inside the agent itself. If we treat agents as autonomous employees, giving them root access and hoping they listen to instructions felt insane to me. I wanted a way to enforce hard constraints that the LLM cannot override, no matter how "jailbroken" it gets. So I built Cordum. It’s an open-source…

    Jan 2026 · github.com

  7. 7LC
  8. 8

    Stop prompt injection from triggering tools.

    Feb 2026

  9. 9FO

    Hey HN, We built FireClaw because we kept watching AI agents get owned by prompt injection through web content. The agent fetches a page, the page says "ignore previous instructions," and suddenly your agent is leaking data or running commands it shouldn't. The existing solutions detect injection after the fact. We wanted to prevent it. FireClaw is a security proxy that sits between your AI agent and the web. Every fetch passes through a 4-stage pipeline: 1. DNS blocklist check (URLhaus, PhishTank, community feed) 2. Structural sanitization (strip hidden CSS, zero-width Unicode, encoding…

    Mar 2026 · github.com

  10. 10FL

    Hi HN! We just launched Codacy Guardrails, an IDE extension with a CLI for code analysis and MCP server that enforces security & quality rules on AI-generated code in real-time. It hooks into AI coding assistants (like VS Code Agent Mode, Cursor, Windsurf), silently scanning and fixing AI-suggested code that has vulnerabilities or violates your coding standards, while the code it’s being generated. We built this because coding agents can be a double-edged sword. They do boost productivity, but can easily introduce insecure or non-compliant code. One recent research team at NYU found that 40%…

    2025

  11. 11

    The AI firewall that understands compliance context

    Dec 2025

  12. 12

    Prompt-injection-safe email for AI agents

    Jul 2026 · postfleet.ai

  13. 13PI

    People seem to be blindly hooking up their OpenClaw’s to their personal data. So, I built runtime controls to prevent at the least, very simple prompt injection attacks. Once installed, it hooks to Node.js child_process module in the gateway process and listens to tool calls and their response streams. And a fetch hook to monitor user prompts (both could’ve been through fetch, happy to discuss why this whole layer couldn’t just be a proxy). There are two layers of protection: First: Whenever there is a read-only tool call whose response an attacker can modify, we extract that part of the…

    Feb 2026 · github.com

  14. 14

    Tiny prompt-injection firewall for LLM chat apps. 14 MB.

    May 2026 · github.com

  15. 15LC

    Prompt instructions like 'never do X' don't hold up in production. LLMs ignore them when context gets long or users push hard. Limits sits between your agent and the real world. Every action — database writes, API calls, refunds — gets intercepted and checked against your rules before it executes. Deterministically. No LLM involved in enforcement. Three modes: Conditions: hard rules on structured data Guideance: validate LLM output before it reaches the user and give the agent chance to reason and retry Guardrails: scan for PII, toxicity, prompt injection etc One line to integrate: npm…

    Feb 2026 · limits.dev

  16. 16

    Open Source deterministic security Firewall for AI agents

    May 2026 · supra-wall.com

  17. 17

    Security firewall for AI agents. Cloudflare for MCP.

    Feb 2026 · agent-wall.github.io

  18. 18IB

    The only way to go fast is full YOLO mode in your coding agent. I've got the local sandbox figured out (pro tip: Incus VMs work great) but I wanted to keep my agents from doing things like inadvertently blowing up my cloud services or chasing a prompt to POST to some random website. I struggle most with this on my side projects where my permission model isn't quite as robust as it is at the office. I started with a firewall on the Incus container but every time the agent needed access to something new, I was poking more holes in it - and it didn't differentiate between HTTP verbs. I've been…

    Jul 2026 · trollbridge.dev

  19. 19

    Runtime firewall for AI coding agents.

    8d ago · contextfence.dev

  20. 20FP

    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

  21. 21

    Stop prompt injection attacks with one API call. Free tier.

    Apr 2026 · safeprompt.dev

  22. 22

    Firewall for AI agents. Scan before you trust.

    Mar 2026 · aisecurityguard.io

  23. 23IM
  24. 24

    Anonymize client docs before you paste them into AI

    Jul 2026 · promptshield.ca

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