# Tool System

## 架构

```mermaid
flowchart LR
    Registry["Tool Registry"] --> Discovery["Discovery"]
    Discovery --> Permission["Permission"]
    Permission --> Validation["Schema Validation"]
    Validation --> Runtime["Execution"]
    Runtime --> Normalize["Result Normalize"]
    Normalize --> Audit["Audit"]
```

## Tool 必须具备

- name
- description
- input schema
- output schema
- permission
- timeout
- retry policy
- version

## 统一原则

Agent 不直接执行任意外部能力。所有工具调用必须经过 Tool Runtime。