---
title: "Firewall an LLM response — verify claims, detect hallucinations, and enforce output policy."
method: POST
path: "/v1/verify"
tags: ["core"]
---

# Firewall an LLM response — verify claims, detect hallucinations, and enforce output policy.

`POST /v1/verify`

## Request

- Base URL: `https://api.agent-toolbox.ai`
- URL: `https://api.agent-toolbox.ai/v1/verify`
- Auth: one of:
  - HTTP bearer
  - none

Cost: 2 credit(s). Free tier: 10 calls per IP (no auth).

## Request body

- VerifyRequest
  - `outputType` 'code' | 'natural_language' | 'agent_action' | 'factual_claim', required
  - `llmResponse` string, required
  - `language` 'python' | 'javascript' | 'typescript' | 'rust' | 'go'
  - `enforcementMode` 'block' | 'flag' | 'audit'
  - `timeoutMs` integer

## Response `200`

Success.

- VerifyResponse
  - `verdict` 'PASS' | 'FLAG' | 'BLOCK', required
  - `overallScore` number, required
  - `claims` object[], required
    - `text` string, required
    - `verdict` 'PASS' | 'FLAG' | 'BLOCK', required
    - `confidence` number, required
    - `checkType` string, required
    - `evidence` string
    - `suggestedFix` string
  - `outputType` 'code' | 'natural_language' | 'agent_action' | 'factual_claim', required
  - `enforcementMode` 'block' | 'flag' | 'audit', required
  - `latencyMs` number, required: Server compute time in ms.
  - `certificate` string, required: Tamper-evident SHA-256 certificate.
  - `importValidation` object
    - `valid` string[], required
    - `hallucinated` string[], required
    - `unknown` string[], required
    - `hallucinationRate` number, required

## Other responses

- `400`: Invalid request body.
- `402`: Free tier exhausted or insufficient credits.

---

[API](https://skmtc.dev/agent-toolbox/apis/agent-toolbox-ai-api.md) · [All operations](https://skmtc.dev/agent-toolbox/apis/agent-toolbox-ai-api/llms.txt) · [OpenAPI document](https://skmtc.dev/agent-toolbox/apis/agent-toolbox-ai-api/revisions/07132043190b?raw)