> ## Documentation Index
> Fetch the complete documentation index at: https://docs.qwedai.tech/llms.txt
> Use this file to discover all available pages before exploring further.

# QWED and Guardrails AI

> How QWED and Guardrails AI differ in mechanism and scope, and how to use them together in an LLM or AI agent stack.

QWED and Guardrails AI work at different points in an AI stack and use different mechanisms. This page compares mechanism and scope, not quality. For what Guardrails AI does, its own documentation is the authority: [guardrailsai.com/docs](https://www.guardrailsai.com/docs).

## What each project says it does

* **Guardrails AI**, in its own docs, runs Input and Output Guards that detect, quantify and mitigate specific types of risk, using validators collected in Guardrails Hub. It also helps generate structured data from LLMs.
* **QWED** checks claims in model and agent output with deterministic engines (SymPy, Z3, SQLGlot, AST analysis and others). A claim is admitted only with a reproducible proof of its formal statement; anything proven false, unprovable or unchecked is denied by default. QWED decides; your integration enforces the decision.

## Mechanism and scope

| | QWED | Guardrails AI |
| - | - | - |
| **How a result is reached** | A deterministic engine proves or disproves a formal statement. No model decides the verdict. | Validators from Guardrails Hub, combined into guards. See its docs for how each validator works. |
| **When a check cannot run** | Fails closed: `UNVERIFIABLE` or `BLOCKED`, both denied. | See its docs. |
| **Coverage** | Domains with a formal statement: math, logic, SQL, code, schema and others listed at [qwedai.tech/engines](https://qwedai.tech/engines). Anything else is `UNVERIFIABLE · DENY`. | The risks its validators cover, plus structured output. |
| **Where it runs** | In your environment: Python library, CLI, self-hosted API or Docker image. | See its docs. |

Guardrails AI covers checks QWED does not try to cover, such as risks with no formal statement to prove. QWED covers proof of formal statements.

## Using both

They can sit in the same pipeline:

1. Guardrails AI guards the input and output, including the response structure.
2. QWED checks the claims inside that structure (a calculation, a SQL query, a tool call) and returns a decision your integration enforces.

QWED verifies the formal statement, not intent, and is only as sound as its engines. See [qwedai.tech/limits](https://qwedai.tech/limits).

## Related docs

* [LLM verification with formal methods](/advanced/llm-verification)
* [QWED vs RAG for LLM verification](/advanced/qwed-vs-rag)
* [QWED vs Guardrails, RAG, and RLHF for LLM verification](/advanced/comparison)
* [QWED Open Responses: verified tool calls for AI agents](/open-responses/overview)


## Related topics

- [QWED vs Guardrails, RAG, and RLHF for LLM verification](/advanced/comparison.md)
- [LLM verification with formal methods](/advanced/llm-verification.md)
- [QWED vs RAG for LLM verification](/advanced/qwed-vs-rag.md)
- [QWED Open Responses: verified tool calls for AI agents](/open-responses/overview.md)
- [QWED Tax: tax verification for AI agents](/tax/overview.md)


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