# MonetizeKit Docs

Discover MonetizeKit documentation for entitlements, usage metering, webhooks, SDKs, and production operations.

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Source: https://learning.monetizekit.app/docs
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Everything you need to add entitlements, usage metering, and billing-aware webhooks to your product — from your first API call to production operations.

## Start here

### Getting Started

Core concepts, authentication, and a runnable first API call.

[Start learning](/docs/getting-started)

### Quickstarts

Pick your framework and run the full happy path in minutes.

[Choose a framework](/docs/quickstarts)

### Guides

Implementation patterns for entitlements, caching, metering, and webhooks.

[Browse guides](/docs/guides)

### Tools & SDKs

The CLI, official SDKs, Postman collection, and AI-assistant integrations.

[Browse tools](/docs/tools)

## Explore guides

Complete, standalone references for the parts of the platform you'll integrate with most.

### Entitlement patterns

Boolean gates, limit checks, and metered entitlements — the verdict model, resolution layering, and caching-safe recheck triggers.

[Open guide](/docs/guides/entitlement-patterns)

### Caching

What the API marks as cacheable, what to cache yourself, and the invalidation events that keep both layers correct.

[Open guide](/docs/guides/caching)

### Metering best practices

Idempotent usage submission, batching high-frequency meters, threshold UX, and drift reconciliation.

[Open guide](/docs/guides/metering)

### Webhook verification and retries

Register endpoints, verify signatures against the raw body, and process retried deliveries idempotently.

[Open guide](/docs/guides/webhooks)

### Migration guide

URL-path versioning, deprecation detection, dual-read fallbacks, and staged rollouts for breaking changes.

[Open guide](/docs/guides/migration)

### Audit and trace

Propagate request IDs end-to-end and correlate API activity, webhook deliveries, and the audit log.

[Open guide](/docs/guides/audit-trace)

### Events & Webhook Explorer

Browse every webhook event type with sample payloads, and verify signatures interactively.

[Open guide](/docs/guides/events)

### Node SDK integration

Enriched decisions with reason codes, batch checks, caching with explicit degradation, credit reservations, and the SDK's two extension points.

[Open guide](/docs/guides/sdk-node)

### Clerk identity integration

Connect your Clerk instance to sync users and organizations as customers, then resolve sessions to customer ids on every request.

[Open guide](/docs/guides/clerk-identity)

### PostHog packaging analytics

Stream entitlement denials into your PostHog project — with explicit identity mapping, volume caps, and a preview of every event before anything is sent.

[Open guide](/docs/guides/posthog-analytics)

### OpenTelemetry visibility

One-line decision spans and bounded metrics on your existing OTel setup, with a deep link from every span to the exact evaluation record.

[Open guide](/docs/guides/opentelemetry)

## Explore by framework

Framework-specific quickstarts with deploy and smoke-test instructions.

### Next.js

TypeScript

[Open quickstart](/docs/quickstarts/nextjs)

### Express

JavaScript

[Open quickstart](/docs/quickstarts/express)

### FastAPI

Python

[Open quickstart](/docs/quickstarts/fastapi)

### Go

Go

[Open quickstart](/docs/quickstarts/go)

### Spring

Java

[Open quickstart](/docs/quickstarts/spring)

## API & GraphQL reference

Once you know what you're integrating, dig into the full endpoint and schema reference.

### API Reference

Browse every REST operation, inspect schemas, run requests, and copy generated snippets.

[Open reference](/docs/api-reference)

### GraphQL Explorer

Browse the complete GraphQL schema and run operations against the interactive explorer.

[Open reference](/docs/graphql)

## Troubleshooting

Diagnose common integration and runtime problems.

### Error Codes

Reference for common API failures and remediation steps.

[Open recovery guide](/docs/troubleshooting/error-codes)

### Auth and Permission Issues

Diagnose invalid keys, scope mismatches, and token lifecycle issues.

[Open recovery guide](/docs/troubleshooting/auth-issues)

### Webhook Delivery Issues

Fix signature mismatches, timeout failures, and endpoint availability problems.

[Open recovery guide](/docs/troubleshooting/webhook-issues)

### Metering and Usage Anomalies

Identify duplicate events, missing events, and threshold misconfiguration.

[Open recovery guide](/docs/troubleshooting/metering-issues)

[See what changed recently in the changelog.](/docs/changelog)