> ## 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 all 64 LimitGuard API endpoints

## Base URL

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

## Authentication

All paid endpoints require one of:

| Method        | Header                       | Description                       |
| ------------- | ---------------------------- | --------------------------------- |
| **API Key**   | `X-API-Key: lg_live_...`     | Subscription-based, monthly quota |
| **x402 USDC** | `X-PAYMENT: <base64>`        | Pay-per-call, no subscription     |
| **Sandbox**   | `X-LimitGuard-Mode: sandbox` | Free testing, 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)                  |
| `X-Response-Quality: enhanced` | Full fan-out + premium sources (most comprehensive) |

## Rate Limits

| Mode              | Limit                        |
| ----------------- | ---------------------------- |
| Sandbox           | 10 requests/minute per IP    |
| Free tier API key | 500 requests/month           |
| Paid API key      | Based on tier                |
| x402 (no key)     | No rate limit (pay per call) |

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

## Endpoint Groups

<CardGroup cols={2}>
  <Card title="Core Trust Intelligence" icon="shield-check">
    Entity checks, risk scoring, KYB verification — the core trust API.
  </Card>

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

  <Card title="Compliance" icon="scale-balanced">
    Regulatory alerts, EU AI Act readiness, and compliance reports.
  </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>