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

# promptguard vs fast-llm-security-guardrails

*GraphCanon updated Sep 20, 2026*

## Verdict

Pick promptguard if promptGuard audits prompts for AI agents to ensure safe code generation; 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.

[promptguard](https://github.com/mturac/promptguard) reports 86 GitHub stars, 1 forks, and 0 open issues, last pushed Jul 22, 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 [promptguard's repository](https://github.com/mturac/promptguard) and [fast-llm-security-guardrails's repository](https://github.com/ZenGuard-AI/fast-llm-security-guardrails).

| | [promptguard](/tools/mturac-promptguard.md) | [fast-llm-security-guardrails](/tools/zenguard-ai-fast-llm-security-guardrails.md) |
| --- | --- | --- |
| Tagline | Audits prompts as behavioral contracts for AI agents. | The fastest Trust Layer for AI Agents |
| Stars | 86 | 155 |
| Forks | 1 | 21 |
| Open issues | 0 | 0 |
| Language | Python | Python |
| Adopt for | PromptGuard audits prompts for AI agents to ensure safe code generation. | 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 | MIT | MIT |
| Categories | AI Agents, Evaluation & Observability | AI Agents, Evaluation & Observability |

## Trust and health

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

| | [promptguard](/tools/mturac-promptguard.md) | [fast-llm-security-guardrails](/tools/zenguard-ai-fast-llm-security-guardrails.md) |
| --- | --- | --- |
| Maintenance | Steady (60%) | Slowing (36%) |
| Days since push | 51d | 222d |
| Stars delta | +5 (30d) | +1 (30d) |
| Owner type | User | Organization |
| Full report | [trust report](/tools/mturac-promptguard/trust.md) | [trust report](/tools/zenguard-ai-fast-llm-security-guardrails/trust.md) |

## Shared compatibility

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

## Decision facts: promptguard

- **Adopt for:** PromptGuard audits prompts for AI agents to ensure safe code generation.

## 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 promptguard if…

- Tags unique to promptguard: audit, prompt-engineering, safety.
- When developing AI agents that generate code and need strict adherence to safety standards
- More recently updated (last pushed Jul 22, 2026).

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

- 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.
- More GitHub stars (155 vs 86) - visibility, not fit.

## When NOT to use promptguard

- If your project does not involve prompting AI for code generation or execution
- In scenarios where real-time prompt auditing is required as it focuses on post-audit analysis

## 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 promptguard and fast-llm-security-guardrails?

promptguard: Audits prompts as behavioral contracts for AI agents.. 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 promptguard over fast-llm-security-guardrails?

Choose promptguard over fast-llm-security-guardrails when Tags unique to promptguard: audit, prompt-engineering, safety; When developing AI agents that generate code and need strict adherence to safety standards; More recently updated (last pushed Jul 22, 2026).

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

Choose fast-llm-security-guardrails over promptguard when 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; More GitHub stars (155 vs 86) - visibility, not fit.

### When should I avoid promptguard?

If your project does not involve prompting AI for code generation or execution In scenarios where real-time prompt auditing is required as it focuses on post-audit analysis

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

fast-llm-security-guardrails has more GitHub stars (155 vs 86). Stars measure visibility, not whether either tool fits your constraints.

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

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

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

GraphCanon lists graph-backed alternatives at [promptguard alternatives](/tools/mturac-promptguard/alternatives) and [fast-llm-security-guardrails alternatives](/tools/zenguard-ai-fast-llm-security-guardrails/alternatives) ([promptguard markdown twin](/tools/mturac-promptguard/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/mturac-promptguard-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, promptguard or fast-llm-security-guardrails?

promptguard: Steady. 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 promptguard and fast-llm-security-guardrails?

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

---

**Machine-readable endpoints**

- JSON: [`/api/graphcanon/graph?tool=mturac-promptguard`](/api/graphcanon/graph?tool=mturac-promptguard)
- 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/_