Product Requirements Document: [Project Name]

AI Context: This document is the PRIMARY source of truth for the AI agent. Read this BEFORE writing any code.

1. Introduction

Purpose: [One sentence describing what this project does]
Target Users: [Who will use this?]
Status: Draft | In Development | Production Ready

2. Goals & Objectives

Functional goal 1: [e.g., "Users can authenticate with email/password"]
Functional goal 2: [e.g., "API response time < 200ms p95"]
Functional goal 3: [e.g., "Support 10k concurrent users"]

3. Tech Stack

Layer	Technology	Version
Frontend	[e.g., React, Vue, vanilla JS]
Backend	[e.g., FastAPI, Node.js, Django]
Database	[e.g., PostgreSQL, SQLite, MongoDB]
Auth	[e.g., JWT, OAuth2, Session]
Testing	[e.g., pytest, Jest, Vitest]
Deployment	[e.g., Docker, Vercel, HF Spaces]

4. Features & Functionality

Feature 1: [Feature Name]

Description: [What it does in 1-2 sentences]
User Story: As a [role], I want [goal], so that [benefit]
Acceptance Criteria:
- Criterion 1
- Criterion 2
API/Interface: [Endpoint or component signature]
Edge Cases: [Error conditions, validation rules]

Feature 2: [Feature Name]

[Repeat structure]

5. Data Models

Entity: User
- id: UUID (primary key)
- email: string (unique, validated)
- password_hash: string (bcrypt)
- created_at: datetime
- updated_at: datetime

Entity: [Next Entity]
- ...

6. API Specification

Endpoint: POST /api/v1/[resource]

Description: [What it does]
Request Body:
```
{
  "field": "type // description"
}
```
Response 200:
```
{
  "id": "uuid",
  "field": "value"
}
```
Response 400/401/404/500: [Error response schema]
Auth Required: Yes/No
Rate Limit: [If applicable]

7. Non-Functional Requirements

Performance: [e.g., p95 latency < 200ms]
Security: [e.g., OWASP Top 10 compliance, input sanitization]
Scalability: [e.g., horizontal scaling strategy]
Accessibility: [e.g., WCAG 2.1 AA]
Browser Support: [e.g., Chrome 110+, Firefox 120+]

8. Constraints & Assumptions

[Assumption 1: e.g., "Users have modern browsers"]
[Constraint 1: e.g., "Must run on single VPS with 2GB RAM"]

9. Open Questions

[Question the AI should clarify before implementing]