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AI · alternatives · 2026

24 alternatives to DKnownAI Guard

AI Agent Security — Prevent Deception, Protect 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 1 we have checked on their own sites, 1 of them free or with a free tier.

  1. 1
    Venn.ai▲336

    Delegate real work to AI agents with safety guardrails

    Mar 2026 · venn.ai · its alternatives →

  2. 2
    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 →

  3. 3
    Guard▲373

    An AI that reads privacy policies for you

    2019 · its alternatives →

  4. 4
    CtrlAI▲104

    Transparent proxy that secures AI agents with guardrails

    Mar 2026 · github.com · its alternatives →

  5. 5

    Configurable safety control for enterprise agent deployment.

    Apr 2026 · elevenlabs.io · its alternatives →

  6. 6

    Your agent team, on your machine. Open-source harness for multi-user Claude agents. - yaodub/cast

    Jun 2026 · github.com · its alternatives →

  7. 7

    Every other gateway is detect-and-block. You don't get a security grade. You don't get red team in CI. We built the one that does. PromptGuard is a proxy: change your base URL (one line with our SDK, or a few lines without), and every request gets checked for prompt injection, PII leaks, jailbreaks, and abuse. 20+ threat vectors, 39+ PII types. We also ship a red team suite and an autonomous agent that mutates attacks to find bypasses - you get a grade (A-F) and a GitHub Action that runs these tests on every PR. So you see where you're weak before you ship. Works with OpenAI, Anthropic,…

    Dec 2025 · promptguard.co · its alternatives →

  8. 8

    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 →

  9. 9

    A pre-execution guard that stops your coding agent running destructive commands. One shell file, no dependencies. - vandith1/agent-guard

    Aug 2026 · github.com · its alternatives →

  10. 10FP

    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 →

  11. 11

    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…

    2025 · archestra.ai · its alternatives →

  12. 12FL

    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 · its alternatives →

  13. 13

    Drop-in security for your AI stack.

    2025 · its alternatives →

  14. 14

    Local security & compliance scanner for AI agents

    Jul 2026 · safeclaude.net · its alternatives →

  15. 15

    Prompt injection detection API for AI agents

    May 2026 · agentshield.pro · its alternatives →

  16. 16

    Stop AI agents from installing malicious packages.

    Jul 2026 · agentinel.habitwala.in · its alternatives →

  17. 17

    Safeguard your prompts before they reach AI

    Dec 2025 · preempt-ai.vercel.app · its alternatives →

  18. 18

    Save 89% of wasted tokens on your AI coding agent

    Mar 2026 · rtk-ai.app · its alternatives →

  19. 19

    Advanced deepfake detection & security

    2025 · its alternatives →

  20. 20

    Scans AI agent skills for malicious code

    Aug 2026 · github.com · its alternatives →

  21. 21

    Block malicious web content before it reaches your AI.

    Jan 2026 · its alternatives →

  22. 22

    Security testing for AI agents

    Mar 2026 · zeroleaks.ai · its alternatives →

  23. 23

    Intercept, protect, and transform AI prompts and responses

    Jan 2026 · ctrlpnl.ai · its alternatives →

  24. 24

    AI is powerful. Make sure it's safe too.

    Jul 2026 · getpreempt.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 →

DKnownAI Guard alternatives (2026): 24 similar tools