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

# Entitlements Overview

> Feature gating and usage limits

Entitlements control what customers can do based on their subscription plan.

**Two types:**

1. **Feature gates** — boolean access (can this customer use analytics? yes/no)
2. **Usage limits** — numeric caps (this customer can make 10,000 API calls/month)

**How it works:**

1. Define features and assign them to plans (in the dashboard or via API)
2. Check access at runtime using can() — in your API (Node/Python SDK) or UI (React useCan hook)
3. Get real-time updates via WebSocket (React SDK auto-subscribes)

**Server-side check:**

```typescript theme={null}
const { allowed, remaining, limit, used } = await nozle.can('cust_123', 'api_calls');
if (!allowed) return res.status(403).json({ error: 'Upgrade required' });
```

**Client-side check:**

```tsx theme={null}
const { allowed, loading } = useCan('cust_123', 'api_calls');
// Or use declarative gates:
<FeatureGate customerId="cust_123" feature="analytics" fallback={<UpgradePrompt />}>
  <Dashboard />
</FeatureGate>
```

**What makes Nozle's entitlements powerful:**

* Real-time WebSocket updates — no polling
* Low-latency cached counters for sub-millisecond checks
* Margin-aware responses (cost/revenue/margin per use)
* React SDK components (FeatureGate, UsageGate, PlanGate, LockedOverlay)