8 Best LLM Guard Alternatives in 2026 (Open Source)
LLM Guard — The Security Toolkit for LLM Interactions.
Short answer
- Closest match to LLM Guard: Guardrails AI.
- Most actively developed: OpenLIT (139 commits in the last 90 days).
- Fastest growing: Guardrails (+217 GitHub stars in the last 30 days).
- No commit in 6+ months: agentic-radar, LangKit and UpTrain.
These 8 open-source tools do the same job. They are ordered by how closely they match LLM Guard, with live GitHub data so you can see which projects are actively maintained.
By package downloads Guardrails is the most used here (446.5K in the last 30 days), even though TensorZero has the most GitHub stars. See all agent tools by downloads.
| Tool | GitHub stars | Stars / 30d | Last commit | Downloads / 30d |
|---|---|---|---|---|
| LLM Guard(original) | 3.2k | +74 | 2026-07-08 | — |
| Guardrails AI | 7.5k | +139 | 2026-08-26 | — |
| Guardrails | 7.2k | +217 | 2026-10-01 | 446.5K |
| agentic-radar | 1.1k | +19 | 2025-11-27 | 5.3K |
| Superagent | 6.8k | +41 | 2026-08-25 | — |
| LangKit | 997 | +3 | 2024-11-22 | — |
| UpTrain | 2.4k | +4 | 2024-07-29 | — |
| OpenLIT | 2.8k | +77 | 2026-10-01 | 5.4K |
| TensorZero | 11.7k | +88 | 2026-06-04 | 37.0K |
1. Guardrails AI
Adding guardrails to large language models.
What sets it apart: Largest ecosystem of pre-built LLM validators (700+ in Hub) with automatic re-prompting — vs Instructor (structured output only) or NeMo Guardrails (conversational focus)
Best for: Adding safety guardrails to LLM outputs in production; Enforcing structured output from any LLM; Teams needing PII detection, toxicity filtering, or format validation
2. Guardrails
NeMo Guardrails is an open-source toolkit for easily adding programmable guardrails to LLM-based conversational systems.
What sets it apart: Only framework offering 5-layer programmable guardrails (input/dialog/retrieval/execution/output) with a dedicated Colang scripting language, backed by NVIDIA
Best for: Enterprise LLM apps needing safety and compliance guardrails; Chatbots requiring strict topic control; RAG pipelines needing retrieval rail filtering
3. agentic-radar
A security scanner for your LLM agentic workflows
What sets it apart: The first dedicated security scanner specifically designed for agentic AI workflows, combining static analysis with runtime adversarial testing and automatic prompt hardening — no other tool maps agent vulnerabilities to OWASP AI security frameworks
Best for: Security teams auditing agentic AI systems before production deployment; DevOps teams integrating AI security scanning into CI/CD pipelines
4. Superagent
Superagent protects your AI applications against prompt injections, data leaks, and harmful outputs. Embed safety directly into your app and prove compliance to your customers.
What sets it apart: YC-backed AI safety SDK that pivoted from general agent building to focused safety tooling — provides guard, redact, and scan capabilities with open-weight models for self-hosting, filling the gap between building agents and securing them
Best for: Teams adding safety layers to production AI agents; Enterprises requiring PII redaction and prompt injection protection; Security-focused AI deployments with compliance requirements
5. LangKit
Open-source text metrics toolkit for monitoring language models through input and output signals
What sets it apart: Open-source text metrics toolkit for LLM monitoring with built-in security detection (jailbreaks, prompt injection), quality scoring, and whylogs integration
Best for: llm-output-monitoring; detecting-prompt-injection; text-quality-observability
6. UpTrain
Open-source platform to evaluate and improve generative AI applications with 20+ preconfigured evaluations
What sets it apart: vs generic eval tools: 20+ preconfigured evaluations with customizable prompts, few-shot examples, and scenario descriptions — all running locally for data privacy with root cause analysis on failures
Best for: RAG system evaluation and quality assurance; LLM application testing before production deployment; Safety and security testing for prompt injection vulnerabilities
7. OpenLIT
Open-source platform for AI agent tracing, evaluations, guardrails, prompts, and GPU monitoring
What sets it apart: Most comprehensive open-source AI engineering platform — combines observability, 11 evaluation types, rule engine, prompt hub, secret vault, playground, and fleet management in one tool
Best for: Teams wanting all-in-one LLM platform (observability + eval + prompts + secrets); Organizations needing self-hosted AI engineering platform; Multi-language teams (Python/TS/Go SDK support)
8. TensorZero
TensorZero is an open-source LLMOps platform that unifies an LLM gateway, observability, evaluation, optimization, and experimentation.
What sets it apart: Only LLM gateway that combines inference, observability, evaluation, and optimization in one Rust-based system with data flywheel — vs LiteLLM (routing only) or Langfuse (observability only)
Best for: Teams wanting a unified LLM gateway with built-in optimization feedback loop; Production systems needing <1ms latency overhead at scale; Organizations wanting to continuously improve LLM performance from production data
FAQ
- What are the best alternatives to LLM Guard?
- The closest open-source alternatives to LLM Guard are Guardrails AI, Guardrails and agentic-radar, followed by Superagent, LangKit and UpTrain. They are ranked by how closely they match what LLM Guard does.
- Which LLM Guard alternative is the most popular?
- TensorZero has the most GitHub stars among LLM Guard alternatives, with 11,716 stars.
- Which LLM Guard alternative is the most actively maintained?
- By recent activity, OpenLIT (139 commits in the last 90 days) is the most actively developed alternative.
Maintain LLM Guard or one of these alternatives?
Each tool page has a maintainer box: a README badge with your live rank and stars, or a homepage feature for $49 / 7 days.
LLM Guard · Guardrails AI · Guardrails · agentic-radar · Superagent · LangKit