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

# API Reference

> Complete reference for every Limitguard API endpoint

## Base URL

```
https://api.limitguard.ai
```

## Authentication

All paid endpoints require one of:

| Method | Header | Description |
| - | - | - |
| **API Key** | `X-API-Key: lg_live_...` | Prepaid balance, debited at list price per call |
| **x402 USDC** | `PAYMENT-SIGNATURE: <base64>` (V1: `X-PAYMENT`) | Pay-per-call, no subscription |
| **Sandbox** | `X-API-Key: lg_sandbox_...` | Free sandbox key from `POST /v1/keys/create` (`"tier": "sandbox"`), mock data |

See [Authentication](/authentication) for full details.

## Request Format

All POST endpoints accept JSON:

```bash theme={null}
curl -X POST https://api.limitguard.ai/v1/entity/check \
  -H "X-API-Key: lg_live_xxxxxxxxxxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{"entity_name": "Acme Corp BV", "country": "NL"}'
```

## Response Format

All responses return JSON with consistent structure. Error responses follow [RFC 7807](https://datatracker.ietf.org/doc/html/rfc7807) problem details:

```json Error Response theme={null}
{
  "type": "about:blank",
  "title": "Validation Error",
  "status": 422,
  "detail": [{"field": "country", "message": "Invalid value"}]
}
```

## Quality Tiers

Control cost vs. freshness on tiered endpoints:

| Header Value | Description |
| - | - |
| `X-Response-Quality: cached` | Serve from cache if available (cheapest) |
| `X-Response-Quality: fresh` | Full data source fan-out (default) |

## Rate Limits

| Mode | Limit |
| - | - |
| Sandbox | 10 requests/minute per IP |
| Free tier API key | 10 / min, 500 / 24 h |
| Paid API key | Based on tier |
| x402 (no key) | 60 / min per payer, no daily cap |

See [Rate Limits](/guides/rate-limits) for details.

## Endpoint Groups

<CardGroup cols={2}>
  <Card title="Lead Verify" icon="user-check" href="/api-reference/leads/lead-verify">
    Check one Dutch or Belgian sales lead against the KVK or KBO register, VIES, sanctions lists and its email domain.
  </Card>

  <Card title="Company checks" icon="shield-check">
    Entity checks, risk scoring and KYB verification.
  </Card>

  <Card title="Reputation" icon="chart-line">
    Trust decay scoring, reputation history, and watchlists.
  </Card>

  <Card title="Compliance" icon="scale-balanced">
    Regulatory alerts and EU AI Act readiness. Per-entity reports are `POST /v1/reports/entity`.
  </Card>

  <Card title="Financial & Treasury" icon="wallet">
    Wallet balances, treasury status, and settlement verification.
  </Card>

  <Card title="Webhooks" icon="bell">
    Register endpoints for real-time event notifications.
  </Card>

  <Card title="Certificates & Badges" icon="certificate">
    Issue, verify, and display trust certificates and badges.
  </Card>
</CardGroup>

## OpenAPI Specification

The full OpenAPI 3.1 specification is available for download:

* **This documentation** is auto-generated from the spec
* **Interactive playground**: test endpoints directly from these docs
* **Code generation**: use the spec with any OpenAPI client generator

<Tip>
  Use the interactive API playground on each endpoint page to test requests directly. Set your API key in the authorization section and make live requests.
</Tip>


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