docs: Update README with API overview, badges, and installation instructions, and refine CHANGELOG entries for clarity and naming consistency.

Author: tercel

CHANGELOG.md

@@ -22,7 +22,7 @@ Built-in `system.*` modules that allow AI agents to query, monitor
 - **`system.control.update_config`** — Runtime config hot-patching with constraint validation.
 - **`system.control.reload_module`** — Hot-reload a module from disk without restart.
 - **`system.control.toggle_feature`** — Enable/disable modules at runtime with reason tracking.
-- **`registerSysModules()`** — Auto-registration wiring for all system modules.
+- **`register_sys_modules()`** — Auto-registration wiring for all system modules.
 
 #### Observability
 - **`ErrorHistory`** — Ring buffer tracking recent errors with deduplication and per-module querying.
@@ -49,7 +49,7 @@ Built-in `system.*` modules that allow AI agents to query, monitor
 - **`ExportProfile`** — Enum for schema export profiles (`mcp`, `openai`, `anthropic`, `generic`).
 
 #### Registry
-- **Module toggle** — `Registry` now supports `disable()`/`enable()` with `ModuleDisabledError` enforcement and event emission.
+- **Module toggle** — APCore client now supports `disable()`/`enable()` for module toggling via `system.control.toggle_feature`, with `ModuleDisabledError` enforcement and event emission.
 - **Version negotiation** — `negotiate_version()` for SDK/module version compatibility checking.
 
 

README.md

@@ -4,6 +4,9 @@
 
 # apcore
 
+![Python](https://img.shields.io/badge/python-3.11+-blue.svg)
+![License](https://img.shields.io/badge/license-Apache%202.0-green.svg)
+
 Schema-driven module development framework for AI-perceivable interfaces.
 
 **apcore** provides a unified task orchestration framework with strict type safety, access control, middleware pipelines, and built-in observability. It enables you to define modules with structured input/output schemas that are easily consumed by LLMs and other automated systems.
@@ -24,6 +27,19 @@ Schema-driven module development framework for AI-perceivable interfaces.
 - **Async task management** -- Background module execution with status tracking, cancellation, and concurrency limiting
 - **W3C Trace Context** -- traceparent header injection/extraction for distributed tracing interop
 
+## API Overview
+
+| Class | Description |
+|-------|-------------|
+| `APCore` | High-level client -- register modules, call, stream, validate |
+| `Registry` | Module storage -- discover, register, get, list, watch |
+| `Executor` | Execution engine -- call with middleware pipeline, ACL, approval |
+| `Context` | Request context -- trace ID, identity, call chain, cancel token |
+| `Config` | Configuration -- load from YAML, get/set values |
+| `ACL` | Access control -- rule-based caller/target authorization |
+| `Middleware` | Pipeline hooks -- before/after/on_error interception |
+| `EventEmitter` | Event system -- subscribe, emit, flush |
+
 ## Documentation
 
 For full documentation, including Quick Start guides for both Python and TypeScript, visit:
@@ -36,10 +52,10 @@ For full documentation, including Quick Start guides for both Python and TypeScr
 ## Installation
 
 ```bash
-pip install -e .
+pip install apcore
 ```
 
-For development:
+### Development
 
 ```bash
 pip install -e ".[dev]"