Dev tools · alternatives · 2026
24 alternatives to AgentShield
AI agent spend firewall
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.
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Kastrafree tier, from $19.99/mo▲332Hi 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 →
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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 →
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Rerun▲301The easiest way to build AI agents for all your tasks
Jul 2026 · rerun.build · its alternatives →
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delegare▲70Hi guys, am building SecureLend.ai and when working on our underwriting agents (free trial, paid after) I had issues with seamless payment options. Of course I looked at x402 which I believe is a great protocol but not a fan of a) sharing private keys with the agent b) having a human in the loop or c) similar workaround e.g. pre-funded wallets So I started building out a solution. For my use case it was important to not only have stablecoins but also a fiat rail which is now implemented using Stripe. Initially I build a mandate system internally but am very glad and big shoutout to the guys…
Apr 2026 · delegare.dev · its alternatives →
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Agentinel▲18Stop AI agents from installing malicious packages.
Jul 2026 · agentinel.habitwala.in · its alternatives →
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Your agents spend autonomously. You set the budget, the vendors, and the limits.
May 2026 · arden.sh · its alternatives →
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The AI agent firewall: catches hijacks that pass every rule
Jul 2026 · agentguard-dusky.vercel.app · its alternatives →
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Hi HN, we're Kiran and Vijay! Over the past two years, we have built a columnar storage engine for observability: logs, metrics, and traces. Today, it's exciting for us to show what we've built on top of that foundation: LLM Agent Observability. Given how non-deterministic agents are, storing all traces without sampling was critical for us. But these traces tend to be in the MBs, sometimes GBs - we needed to store them inexpensively. We also needed the queries and analyses to be fast. To meet both these goals, we store them in S3 in our own parquet-like file format, and query them using AWS…
Jul 2026 · oodle.ai · its alternatives →
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Tl;dr: I trained a classifier to route to the least expensive model and reasoning depth to complete the request. Coupling that with additional automated token efficiency techniques has yielded 3x usage for the same spend. For anyone interested in trying it themselves: https://nerfguard.com Various teammates and I switched over to Codex from Claude Code recently. We still bounce between the tools, but Codex’s speed and steerability coupled with performance gains were hard to ignore. One of the downsides was that the per token pricing kicked in way sooner. This is happening across…
Jun 2026 · its alternatives →
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AgentWatch▲12Hi 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 →
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As a Security Engineer with over 10+ years in industry, I kept running into the same problem with coding agents: Instructions are not guarantees. I put guidance in `CLAUDE.md`, `AGENTS.md`, memory files, MCP descriptions, and tool documentation. I explicitly told the agent things like: - Use the code graph for architecture questions instead of grepping the repository. - Do not use deprecated APIs or Unsafe code. - Prefer specific tools for specific tasks. The agent would still ignore those instructions surprisingly often. It would grep the entire repo, use deprecated APIs, or choose a slower…
Apr 2026 · sigmashake.com · its alternatives →
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Deterministic offline release evidence for AI agents
Jul 2026 · iisacc-justmoong.github.io · its alternatives →
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Hey HN, I built AgentBudget after an AI agent loop cost me $187 in 10 minutes — GPT-4o retrying a failed analysis over and over. Existing tools (LangSmith, Langfuse) track costs after execution but don't prevent overspend. AgentBudget is a Python SDK that gives each agent session a hard dollar budget with real-time enforcement. Integration is two lines: import agentbudget agentbudget.init("$5.00") It monkey-patches the OpenAI and Anthropic SDKs (same pattern as Sentry/Datadog), so existing code works without changes. When the budget is hit, it raises BudgetExhausted before the next API…
Feb 2026 · github.com · its alternatives →
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Hi HN, I built AgenTank. It is a small game where an AI agent writes the logic for your tank. You watch it fight, give strategic feedback, let the agent update the tank code, and send it back into battle. I have run 1,000+ battles on my own tank and spent about $200 in Claude credits improving it. The part I enjoy most is not just winning, but watching the tank make visible mistakes, thinking of a better strategy, and seeing whether Claude can turn that into better code.
May 2026 · agentank.ai · its alternatives →
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Real-time cost enforcement for AI Agents
Mar 2026 · agentbudget.dev · its alternatives →
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Runwallfree tier▲9A Runtime security layer that lets AI agents execute safely
Jul 2026 · runwall.vercel.app · its alternatives →
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FuseBox▲2Stop runaway AI agent costs with one line of Python
Jun 2026 · swarmsmart.gumroad.com · its alternatives →
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We built meta-agent: an open-source library that automatically and continuously improves agent harnesses from production traces. Point it at an existing agent, a stream of unlabeled production traces, and a small labeled holdout set. An LLM judge scores unlabeled production traces as they stream. A proposer reads failed traces and writes one targeted harness update at a time, such as changes to prompts, hooks, tools, or subagents. The update is kept only if it improves holdout accuracy. On tau-bench v3 airline, meta-agent improved holdout accuracy from 67% to 87%. We open-sourced meta-agent.…
Apr 2026 · github.com · its alternatives →
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Runtime firewall for AI coding agents.
Aug 2026 · contextfence.dev · its alternatives →
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Gateplex▲12Real-time governance firewall for autonomous AI agents
May 2026 · gateplex.ai · 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 →