# Full Technical Specification & Architecture: MySpec.dev

## What is Spec-Driven Development (SDD)?
Spec-Driven Development (SDD) is an AI-first software engineering methodology where structured, version-controlled technical specifications (`constitution.md`, `requirements.md`, `solution.md`, `tasks.md`) precede code generation to eliminate hallucinations and scope creep.

## The 4-File Spec Bundle Hierarchy
1. `constitution.md`: Non-negotiable technical constraints (TypeScript strict mode, framework versions, styling rules, forbidden packages).
2. `requirements.md`: EARS+ formatted functional requirements with explicit acceptance criteria.
3. `solution.md`: Architecture diagrams (Mermaid.js), database models (Postgres, Drizzle, Prisma), API route signatures.
4. `tasks.md`: Atomic, ordered development tasks that execute within optimal LLM token windows.

## EARS Requirements Syntax Patterns
1. Ubiquitous: The <system> shall <response>.
2. Event-Driven: WHEN <trigger>, the <system> shall <response>.
3. State-Driven: WHILE <state>, the <system> shall <response>.
4. Unwanted Behavior: IF <error/condition>, THEN the <system> shall <response>.
5. Optional Feature: WHERE <feature>, the <system> shall <response>.

## Connecting via Model Context Protocol (MCP)
Install `@myspec/mcp-server` over stdio in Claude Code / Cursor Composer:
```json
{
  "mcpServers": {
    "myspec": {
      "command": "npx",
      "args": ["-y", "@myspec/mcp-server"]
    }
  }
}
```
Available tools:
- `get_constitution`: Returns active tech stack rules
- `get_requirements`: Returns EARS functional criteria
- `get_solution`: Returns architecture diagrams and schemas
- `get_tasks`: Returns task list with progress markers
- `update_task`: Marks task as completed with Git diff reference