---
title: "prismor vs fast-llm-security-guardrails"
type: "comparison"
canonical_url: "https://www.graphcanon.com/compare/prismorsec-prismor-vs-zenguard-ai-fast-llm-security-guardrails"
tools: ["prismorsec-prismor", "zenguard-ai-fast-llm-security-guardrails"]
---

# prismor vs fast-llm-security-guardrails

*GraphCanon updated Sep 20, 2026*

## Verdict

Pick prismor if prismor is a runtime firewall that safeguards AI frameworks against security breaches like prompt injection attacks and secret leaks. It supports Claude Code and Codex; pick fast-llm-security-guardrails if fast-llm-security-guardrails, also known as ZenGuard, is designed for the rapid deployment of security measures into AI agent systems to ensure they operate within defined trust constraints.

[prismor](https://prismor.dev) reports 343 GitHub stars, 35 forks, and 46 open issues, last pushed Sep 11, 2026. [fast-llm-security-guardrails](https://zenguard.ai/) has 155 stars, 21 forks, and 0 open issues, last pushed Feb 3, 2026. Figures are from public GitHub metadata via [prismor's repository](https://github.com/PrismorSec/prismor) and [fast-llm-security-guardrails's repository](https://github.com/ZenGuard-AI/fast-llm-security-guardrails).

| | [prismor](/tools/prismorsec-prismor.md) | [fast-llm-security-guardrails](/tools/zenguard-ai-fast-llm-security-guardrails.md) |
| --- | --- | --- |
| Tagline | Runtime firewall for AI agents to prevent rogue tool calls and security breaches | The fastest Trust Layer for AI Agents |
| Stars | 343 | 155 |
| Forks | 35 | 21 |
| Open issues | 46 | 0 |
| Language | Python | Python |
| Adopt for | Prismor is a runtime firewall that safeguards AI frameworks against security breaches like prompt injection attacks and secret leaks. It supports Claude Code and Codex. | fast-llm-security-guardrails, also known as ZenGuard, is designed for the rapid deployment of security measures into AI agent systems to ensure they operate within defined trust constraints. |
| Persona | - | - |
| Runtime | - | - |
| License | Apache-2.0, permissive open-source license allowing free use and distribution under certain conditions. | MIT |
| Categories | AI Agents, Evaluation & Observability | AI Agents, Evaluation & Observability |

## Trust and health

_Sourced signals - not a safety guarantee. No winner column._

| | [prismor](/tools/prismorsec-prismor.md) | [fast-llm-security-guardrails](/tools/zenguard-ai-fast-llm-security-guardrails.md) |
| --- | --- | --- |
| Maintenance | Very active (96%) | Slowing (36%) |
| Days since push | 0d | 222d |
| Open issues (now) | 46 | 0 |
| Stars delta | +63 (30d) | +1 (30d) |
| Open issues delta | +34 (30d) | 0 (30d) |
| Full report | [trust report](/tools/prismorsec-prismor/trust.md) | [trust report](/tools/zenguard-ai-fast-llm-security-guardrails/trust.md) |

## Shared compatibility

- **Python**: [prismor](/tools/prismorsec-prismor.md) - Python runtime; [fast-llm-security-guardrails](/tools/zenguard-ai-fast-llm-security-guardrails.md) - Python runtime

## Decision facts: prismor

- **Pricing:** freemium - Free with a commercial license for advanced features.
- **Requirements:** Min 1 GB RAM
- **Adopt for:** Prismor is a runtime firewall that safeguards AI frameworks against security breaches like prompt injection attacks and secret leaks. It supports Claude Code and Codex.
- **License detail:** Apache-2.0, permissive open-source license allowing free use and distribution under certain conditions.

## Decision facts: fast-llm-security-guardrails

- **Adopt for:** fast-llm-security-guardrails, also known as ZenGuard, is designed for the rapid deployment of security measures into AI agent systems to ensure they operate within defined trust constraints.

## Choose when

### Choose prismor if…

- License: prismor is Apache-2.0, fast-llm-security-guardrails is MIT.
- Pricing: Free with a commercial license for advanced features..
- Requirements: Min 1 GB RAM.
- Tags unique to prismor: agent-security, llm-security, prompt-injection, security-tools.
- When you need a dedicated firewall for AI tools to block unauthorized calls.

### Choose fast-llm-security-guardrails if…

- License: fast-llm-security-guardrails is MIT, prismor is Apache-2.0.
- Tags unique to fast-llm-security-guardrails: agentic-ai, ai-agent, ai-runtime, cx-agent.
- Fast integration of privacy and security guardrails in environments where real-time evaluation and observability are critical.

## When NOT to use prismor

- Avoid if you do not use supported frameworks like Claude Code or Codex, as it might lack coverage.
- Not suitable if you prioritize open-source contributions over runtime protection.

## When NOT to use fast-llm-security-guardrails

- If your project requires a more customizable solution than what fast-llm-security-guardrails offers in its out-of-the-box configurations.
- For teams that operate without established runtime environments like LangChain or LlamaIndex, as this may necessitate significant adaptation of ZenGuard.

## Common questions

### What is the difference between prismor and fast-llm-security-guardrails?

prismor: Runtime firewall for AI agents to prevent rogue tool calls and security breaches. fast-llm-security-guardrails: The fastest Trust Layer for AI Agents. See the comparison table for live GitHub stats and shared categories.

### When should I choose prismor over fast-llm-security-guardrails?

Choose prismor over fast-llm-security-guardrails when License: prismor is Apache-2.0, fast-llm-security-guardrails is MIT; Pricing: Free with a commercial license for advanced features.; Requirements: Min 1 GB RAM; Tags unique to prismor: agent-security, llm-security, prompt-injection, security-tools; When you need a dedicated firewall for AI tools to block unauthorized calls.

### When should I choose fast-llm-security-guardrails over prismor?

Choose fast-llm-security-guardrails over prismor when License: fast-llm-security-guardrails is MIT, prismor is Apache-2.0; Tags unique to fast-llm-security-guardrails: agentic-ai, ai-agent, ai-runtime, cx-agent; Fast integration of privacy and security guardrails in environments where real-time evaluation and observability are critical.

### When should I avoid prismor?

Avoid if you do not use supported frameworks like Claude Code or Codex, as it might lack coverage. Not suitable if you prioritize open-source contributions over runtime protection.

### When should I avoid fast-llm-security-guardrails?

If your project requires a more customizable solution than what fast-llm-security-guardrails offers in its out-of-the-box configurations. For teams that operate without established runtime environments like LangChain or LlamaIndex, as this may necessitate significant adaptation of ZenGuard.

### Is prismor or fast-llm-security-guardrails more popular on GitHub?

prismor has more GitHub stars (343 vs 155). Stars measure visibility, not whether either tool fits your constraints.

### Are prismor and fast-llm-security-guardrails open source?

Yes - both are open-source projects on GitHub (prismor: Apache-2.0, fast-llm-security-guardrails: MIT).

### Where can I find alternatives to prismor or fast-llm-security-guardrails?

GraphCanon lists graph-backed alternatives at [prismor alternatives](/tools/prismorsec-prismor/alternatives) and [fast-llm-security-guardrails alternatives](/tools/zenguard-ai-fast-llm-security-guardrails/alternatives) ([prismor markdown twin](/tools/prismorsec-prismor/alternatives.md), [fast-llm-security-guardrails markdown twin](/tools/zenguard-ai-fast-llm-security-guardrails/alternatives.md)), ranked by typed relationship edges rather than popularity votes.

### Is there a machine-readable version of this comparison?

Yes. The markdown twin at [this comparison](/compare/prismorsec-prismor-vs-zenguard-ai-fast-llm-security-guardrails.md) mirrors this page for agents and LLM crawlers, with the same stats table and FAQ answers.

### Which is better maintained, prismor or fast-llm-security-guardrails?

prismor: Very active. fast-llm-security-guardrails: Slowing. Compare maintenance labels, days since push, and release cadence in the trust section below - stars alone do not measure maintenance.

### Where are the full trust reports for prismor and fast-llm-security-guardrails?

GraphCanon publishes per-repo trust reports with dated maintenance, provenance, and scan summaries: [prismor trust report](/tools/prismorsec-prismor/trust); [fast-llm-security-guardrails trust report](/tools/zenguard-ai-fast-llm-security-guardrails/trust).

---

**Machine-readable endpoints**

- JSON: [`/api/graphcanon/graph?tool=prismorsec-prismor`](/api/graphcanon/graph?tool=prismorsec-prismor)
- LLM index: [/llms.txt](/llms.txt)
- Full corpus: [/llms-full.txt](/llms-full.txt)

_GraphCanon - The knowledge graph for AI development. https://www.graphcanon.com/_