hook-event-architecture

# Hook Event Architecture

Design hook-based event systems for capturing and broadcasting agent activities in AI Developer Workflows.

## MANDATORY: docs-management Delegation

> **Documentation Verification:** This skill references Claude Code hook events and configuration
> that may change between releases. Before implementing, invoke `hook-management` skill to verify
> current event types and hook configuration patterns.

**Verification Checkpoint:**

- [ ] Did I invoke `hook-management` for current event types?
- [ ] Did official documentation confirm the event schema?
- [ ] Is my implementation based on official docs?

## When to Use

- Implementing real-time event broadcasting
- Building observability infrastructure
- Creating swimlane visualizations
- Logging agent activities to database
- Generating AI-powered event summaries

## Prerequisites

- Understanding of Claude Code hooks (@hook-event-patterns.md)
- Familiarity with WebSocket patterns (@websocket-architecture.md)
- Access to Claude Agent SDK for full implementation

## SDK Requirement

> **Implementation Note**: Full hook event architecture requires Claude Agent SDK with custom tooling. This skill provides design patterns and specifications.

## Event Types

> **Documentation Verification:** The event types listed here are Claude Code internal types that may change between releases. For authoritative current event types, query the `hook-management` skill which delegates to `docs-management` for official documentation.

ADW systems capture these event types:

| Event Type | Icon | Source | Payload |
| --- | --- | --- | --- |
| `PreToolUse` | 🪝 | Hook | Tool name, inputs, session |
| `PostToolUse` | 🪝 | Hook | Tool name, outputs, duration |
| `TextBlock` | 💬 | Agent | Response text, tokens |
| `ToolUseBlock` | 🛠️ | Agent | Tool invocation record |
| `ThinkingBlock` | 🧠 | Agent | Extended thinking content |
| `StepStart` | ⚙️ | System | Step name, inputs |
| `StepEnd` | ⚙️ | System | Step name, ou