vinvcn 文档和 ADR
概览
记录决策，而不只是记录代码。最有价值的文档会捕捉 why：促成某个决策的上下文、约束和权衡。代码展示构建了 what；文档解释 why it was built this way，以及 what alternatives were considered。这些上下文对未来在代码库中工作的工程师和 agent 都很重要。
何时使用
- 做出重要架构决策
- 在多个竞争方案之间做选择
- 添加或变更公开 API
- 发布会改变用户可见行为的功能
- 让新的团队成员（或 agent）熟悉项目
- 当你发现自己反复解释同一件事时
不应使用的情况： 不要记录显而易见的代码。不要添加只是复述代码本身的注释。不要为一次性原型编写文档。
Architecture Decision Records (ADRs，架构决策记录)
ADR 捕捉重大技术决策背后的推理。它们是你能写出的最高价值文档。
何时编写 ADR
- 选择框架、库或主要依赖
- 设计数据模型或数据库 schema
- 选择认证策略
- 决定 API 架构（REST vs. GraphQL vs. tRPC）
- 在构建工具、托管平台或基础设施之间做选择
- 任何逆转成本高的决策
ADR 模板
将 ADR 存放在 docs/decisions/，并使用连续编号：
# ADR-001: Use PostgreSQL for primary database
## Status
Accepted | Superseded by ADR-XXX | Deprecated
## Date
2025-01-15
## Context
We need a primary database for the task management application. Key requirements:
- Relational data model (users, tasks, teams with relationships)
- ACID transactions for task state changes
- Support for full-text search on task content
- Managed hosting available (for small team, limited ops capacity)
## Decision
Use PostgreSQL with Prisma ORM.
## Alternatives Considered
### MongoDB
- Pros: Flexible schema, easy to start with
- Cons: Our data is inherently relational; would need to manage relationships manually
- Rejected: Relational data in a document store leads to complex joins or data duplication
### SQLite
- Pros: Zero configuration, embedded, fast for reads
- Cons: Limited concurrent write support, no managed hosting for production
- Rejected: Not suitable for multi-user web application in production
### MySQL
- Pros: Mature, widely supported
- Cons: PostgreSQL has better JSON support, full-text search, and ecosystem tooling
- Rejected: PostgreSQL is the better fit for our feature requirements
## Consequences
- Prisma provides type-safe database access and migration management
- We can use PostgreSQL's full-text search instead of adding Elasticsearch
- Team needs PostgreSQL knowledge (standard skill, low risk)
- Hosting on managed service (Supabase, Neon, or RDS)
ADR 生命周期
PROPOSED → ACCEPTED → (SUPERSEDED or DEPRECATED)
- 不要删除旧 ADR。 它们捕捉历史上下文。
- 当决策发生变化时，写一个新的 ADR，引用并取代旧 ADR。
行内文档
何时写注释
注释解释 why，而不是 what：
// BAD: Restates the code
// Increment counter by 1
counter += 1;
// GOOD: Explains non-obvious intent
// Rate limit uses a sliding window — reset counter at window boundary,
// not on a fixed schedule, to prevent burst attacks at window edges
if (now - windowStart > WINDOW_SIZE_MS) {
counter = 0;
windowStart = now;
}
何时不要写注释
// Don't comment self-explanatory code
function calculateTotal(items: CartItem[]): number {
return items.reduce((sum, item) => sum + item.price * item.quantity, 0);
}
// Don't leave TODO comments for things you should just do now
// TODO: add error handling ← Just add it
// Don't leave commented-out code
// const oldImplementation = () => { ... } ← Delete it, git has history
记录已知陷阱
/**
* IMPORTANT: This function must be called before the first render.
* If called after hydration, it causes a flash of unstyled content
* because the theme context isn't available during SSR.
*
* See ADR-003 for the full design rationale.
*/
export function initializeTheme(theme: Theme): void {
// ...
}
API 文档
对于公开 API（REST、GraphQL、库接口）：
与类型一起内联记录（TypeScript 首选）
/**
* Creates a new task.
*
* @param input - Task creation data (title required, description optional)
* @returns The created task with server-generated ID and timestamps
* @throws {ValidationError} If title is empty or exceeds 200 characters
* @throws {AuthenticationError} If the user is not authenticated
*
* @example
* const task = await createTask({ title: 'Buy groceries' });
* console.log(task.id); // "task_abc123"
*/
export async function createTask(input: CreateTaskInput): Promise<Task> {
// ...
}
REST API 使用 OpenAPI / Swagger
paths:
/api/tasks:
post:
summary: Create a task
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/CreateTaskInput'
responses:
'201':
description: Task created
content:
application/json:
schema:
$ref: '#/components/schemas/Task'
'422':
description: Validation error
README 结构
每个项目都应该有一份 README，覆盖：
# Project Name
One-paragraph description of what this project does.
## Quick Start
1. Clone the repo
2. Install dependencies: `npm install`
3. Set up environment: `cp .env.example .env`
4. Run the dev server: `npm run dev`
## Commands
| Command | Description |
|---------|-------------|
| `npm run dev` | Start development server |
| `npm test` | Run tests |
| `npm run build` | Production build |
| `npm run lint` | Run linter |
## Architecture
Brief overview of the project structure and key design decisions.
Link to ADRs for details.
## Contributing
How to contribute, coding standards, PR process.
Changelog 维护
对于已发布功能：
# Changelog
## [1.2.0] - 2025-01-20
### Added
- Task sharing: users can share tasks with team members (#123)
- Email notifications for task assignments (#124)
### Fixed
- Duplicate tasks appearing when rapidly clicking create button (#125)
### Changed
- Task list now loads 50 items per page (was 20) for better UX (#126)
面向 Agent 的文档
需要特别考虑 AI agent 的上下文：
- CLAUDE.md / rules files — 记录项目约定，让 agent 遵循它们
- Spec files — 保持 spec 更新，让 agent 构建正确的东西
- ADRs — 帮助 agent 理解过去决策的原因（避免重复决策）
- Inline gotchas — 防止 agent 掉入已知陷阱
常见合理化借口
| 合理化借口 | 现实 |
|---|---|
| “代码是自解释的” | 代码展示 what。它不展示 why、不展示哪些替代方案被拒绝，也不展示适用哪些约束。 |
| “等 API 稳定后再写文档” | 当你记录 API 时，API 会更快稳定下来。文档是设计的第一道测试。 |
| “没人读文档” | Agent 会读。未来工程师会读。三个月后的你也会读。 |
| “ADR 是额外负担” | 一份 10 分钟写完的 ADR，可以避免六个月后围绕同一决策进行 2 小时争论。 |
| “注释会过时” | 关于 why 的注释是稳定的。关于 what 的注释会过时，所以只写前者。 |
危险信号
- 架构决策没有书面理由
- 公开 API 没有文档或类型
- README 没有说明如何运行项目
- 用注释掉的代码代替删除
- TODO 注释已经存在数周
- 有重大架构选择的项目中没有 ADR
- 文档只是复述代码，而不是解释意图
验证
完成文档后：
- 所有重大架构决策都有 ADR
- README 覆盖 quick start、commands 和 architecture overview
- API 函数有参数和返回类型文档
- 已知陷阱在重要位置以内联方式记录
- 没有保留注释掉的代码
- Rules files（CLAUDE.md 等）是最新且准确的