Reference
Technical specifications for Hook0. Use this reference when you need exact details about APIs, configuration options, data formats, or error codes.
Quick Navigation
| I want to... | Go to |
|---|---|
| Integrate with the API | API Reference |
| Use a client library | SDKs |
| Configure Hook0 | Configuration |
| Understand an error | Error Codes |
| Define event payloads | Event Schemas |
| Use AI assistants | MCP Server |
| Use the CLI | CLI Reference |
API Reference
REST API Documentation
Complete API specification with all endpoints, request/response formats, and authentication details.
Available formats:
- OpenAPI 3.0 Specification — Machine-readable, import into tools
- Interactive Swagger UI — Available at
/docson your Hook0 instance
Key endpoints:
| Resource | Operations |
|---|---|
| Organizations | List, get |
| Applications | Create, list, get, delete |
| Event Types | Create, list, get, delete |
| Subscriptions | Create, list, get, update, delete |
| Events | Ingest, list, get, replay |
| Request Attempts | List, get |
SDKs
Client libraries for integrating Hook0 into your applications.
| Language | Package | Install from |
|---|---|---|
| JavaScript/TypeScript | hook0-client | npm |
| Rust | hook0-client | crates.io |
| Python | hook0-client | PyPI |
| Ruby | hook0-client | RubyGems |
| C# / .NET | Hook0.Client | NuGet |
| Go | github.com/hook0/hook0-go/v2 | Go module proxy |
| PHP | hook0/client | Packagist |
| Java | com.hook0:hook0-client | source |
| Kotlin | com.hook0:hook0-client-kotlin | source |
| Lua | hook0-client | source |
| Zig | hook0_client | tagged archive |
Each page says how to install the client, how to send an event, and how to verify a webhook signature. See SDKs & client libraries for what they share.
Configuration
Configuration Reference
All environment variables and configuration options for Hook0 server and worker processes.
Data Formats
Event Schemas
Standardized payload structures and validation rules for your event types.
Error Codes
Complete list of HTTP status codes and Hook0-specific error codes with resolution steps.
AI Assistant Integration
MCP Server for AI Assistants
Control Hook0 using natural language with Claude, Cursor, Windsurf, or any MCP-compatible AI assistant.
CLI
CLI Reference
Command-line interface for managing webhooks, forwarding events locally, and interacting with the Hook0 API.
Key capabilities:
- Forward webhooks to localhost via WebSocket tunnel (
hook0 listen) - Send test events with an interactive TUI (
hook0 example) - Manage events, subscriptions, and applications
- Replay failed events with filtering
Related Documentation
- Tutorials — Step-by-step learning guides
- How-to Guides — Task-oriented problem solving
- Explanation — Conceptual understanding