Cursor AI Editor: Complete Guide for Developers & Product Managers

Master the AI-first code editor with Composer model, multi-agent workflows, and production-ready development. Learn from basics to advanced techniques with Cursor 2.0.

24 min read

Beginner to Advanced

Updated Nov 2025

Oct 2025

Cursor 2.0 + Composer Released

4x Faster

Composer vs similar models

8 Agents

Parallel multi-agent support

What You'll Learn

Master Composer model and multi-agent workflows
Configure .cursor/rules for project conventions
Use Ask, Edit, and Agent modes effectively
Automate browser testing and workflows
Implement production-ready development patterns
Optimize context and voice control features

What is Cursor?

Cursor is an AI-first code editor built from the ground up for AI-assisted development. Unlike traditional editors with AI plugins, Cursor reimagines the entire coding experience around AI collaboration, featuring its own frontier model (Composer) and multi-agent architecture.

The Cursor 2.0 Revolution (October 2025)

Cursor 2.0 introduced Composer—their first coding model built with reinforcement learning—and a revolutionary multi-agent interface that can run 8 agents in parallel. This shift represents moving from "AI-assisted coding" to true "multi-agent development."

Where Cursor Excels

• AI-first editor design (not a plugin)
• Custom Composer model (4x faster)
• Multi-agent parallel workflows
• Codebase-wide context awareness
• Browser automation built-in
• Voice control and natural interaction

Key Differentiators

• Composer model (proprietary)
• 8 parallel agents with git worktrees
• .cursor/rules configuration system
• Built-in browser agent
• Plan-before-code workflows
• Mixture-of-experts architecture

ELI5: Cursor

Imagine your code editor is actually designed for AI collaboration from day one, not as an afterthought. Instead of typing code manually while AI suggests lines, you work alongside AI as a team.

The multi-agent magic: You can have 8 different AI agents working on different parts of your project at the same time—like having 8 pair programmers who never get tired. Each one works in its own copy of the code so they don't mess each other up.

Composer is Cursor's own AI brain—4x faster than other coding AIs and specifically trained to write code that actually works, not just looks good.

Getting Started

Installation

1
Download Cursor
Visit cursor.com and download for macOS, Windows, or Linux
2
Import VS Code Settings (Optional)
Cursor can import your VS Code extensions and settings for a seamless transition
3
Sign Up for Pro (Recommended)
$20/month for unlimited Composer access, priority responses, and advanced features
4
Open a Project
Try: Cmd/Ctrl+K to open Composer and ask "Explain this codebase"

Essential Shortcuts:

Cmd/Ctrl+K → Composer (Agent mode)

Cmd/Ctrl+L → Chat sidebar

Cmd/Ctrl+I → Inline edit

Cmd/Ctrl+Shift+P → Command palette

Composer Model: Cursor's AI Brain

Composer is Cursor's proprietary frontier model, purpose-built for low-latency agentic coding. Released in October 2025, it's 4x faster than similarly intelligent models and completes most coding tasks in under 30 seconds.

Technical Architecture

Mixture-of-Experts (MoE) - Dynamically routes queries to specialized sub-models for optimal performance
Reinforcement Learning Training - Trained using RL with custom tools (semantic search, structured feedback loops)
Long-Context Generation - Understands and generates across entire codebases, not just files

When to Use Composer vs Other Models:

Cursor lets you choose your model. Here's when to use each:

• Composer - Default for all coding tasks (fastest, best for code)
• Claude Sonnet 4.5 - Complex reasoning, architectural decisions
• GPT-5.1 Instant - Latest from OpenAI with adaptive reasoning and conversational tone (Nov 2025)
• GPT-5.1 Thinking - Advanced reasoning for complex problems, faster on simple tasks (Nov 2025)
• Opus 4 - Deep refactoring across large codebases

Three Interaction Modes

Ask Mode (Cmd/Ctrl+L)

Chat sidebar for questions and code exploration. Perfect for understanding codebases, debugging, and learning.

Best for:

• "Explain how authentication works in this project"
• "What does this function do?"
• "How should I structure this feature?"
• "Find all usages of UserModel"

Edit Mode (Cmd/Ctrl+I)

Inline edits for quick, focused changes. Like AI pair programming directly in your file.

Best for:

• "Add error handling to this function"
• "Convert this to TypeScript"
• "Add JSDoc comments"
• "Optimize this SQL query"

Agent Mode (Cmd/Ctrl+K) - DEFAULT

Composer with full tools and reasoning. Can plan, execute across files, run terminal commands, and use browser automation.

Advanced Capabilities:

• Multi-file refactoring
• Terminal command execution
• Browser automation for testing
• Codebase-wide semantic search
• Plan generation before coding
• Long-running autonomous tasks

Multi-Agent Workflows

Cursor 2.0's breakthrough feature: run up to 8 agents in parallel on a single prompt. Each agent operates in an isolated copy of your codebase using git worktrees or remote workers.

How It Works

1.Give a complex task: "Implement user authentication with OAuth, email verification, and password reset"
2.Composer analyzes and spawns multiple agents for parallel work
3.Agent 1 works on OAuth integration, Agent 2 on email service, Agent 3 on frontend forms, etc.
4.Each agent uses its own git worktree—no conflicts, complete isolation
5.Review and merge each agent's work independently

Production Tip: Git Worktrees

Cursor uses git worktrees to give each agent its own workspace. This means you can have 8 agents refactoring different parts of your codebase simultaneously without merge conflicts. Each completes independently and you review/merge as needed.

.cursor/rules: Project Configuration

The .cursor/rules system lets you encode project conventions, forbidden patterns, and preferred libraries so Composer always follows your team's standards.

Example: .cursor/rules/index.mdc

---
title: Project Rules
type: rule
alwaysApply: true
---

# Code Style
- Use TypeScript strict mode
- Prefer functional components in React
- Use Tailwind CSS (no inline styles)
- All functions must have TypeScript types

# Testing
- Write tests BEFORE implementation (TDD)
- Use Jest for unit tests, Playwright for E2E
- Minimum 80% code coverage required

# Security
- Never commit .env files
- All API keys via environment variables
- Use Zod for input validation
- Sanitize all user inputs

# Forbidden
- Do not use 'any' type in TypeScript
- No jQuery or outdated libraries
- Avoid inline CSS styles
- Never use var (use const/let)

# Architecture
- Next.js 15 App Router only
- Supabase for backend
- React Query for data fetching
- Server actions for mutations

Community Resources

• cursor.directory - Browse community rules
• dotcursorrules.com - Curated rule templates
• awesome-cursorrules - GitHub repository of examples

Browser for Agent (GA)

Graduated from beta to general availability in Cursor 2.0. Agents can now control a browser directly within the editor for automated testing, scraping, and web workflows.

Use Cases:

E2E Testing - "Test the login flow and take screenshots of each step"
Web Scraping - "Extract pricing from competitor websites"
Form Testing - "Fill out the registration form with test data"
Visual Debugging - "Click through the user journey and show me the network calls"

Pro Tip: Browser agent can select elements and forward DOM information to Composer, enabling precise UI testing and automation without writing Playwright code manually.

Production Best Practices

1. Use Git as Your Safety Net

Critical Rule:

Treat git as your undo button. Create feature branches, commit frequently, and make small PRs. AI-generated code should always be reversible.

git checkout -b feature/ai-generated before major changes

2. Keep Prompts Scoped and Contextual

❌ Vague:

"Refactor the code"

✅ Specific:

"Refactor src/auth/login.ts to use async/await instead of promises. Keep error handling patterns consistent with src/auth/signup.ts"

3. Start Fresh When Stuck

AI context windows are limited. If you're in a loop or the agent is confused, start a new conversation with refined requirements. Don't try to "fix" a broken conversation—restart with better context.

4. Set Up MCPs + Rules + Memories Early

At the start of every project:

• Configure .cursor/rules with project conventions
• Add relevant MCP servers (GitHub, Linear, databases)
• Let Cursor build "memories" of your preferences
• Run auto-configuration at project start

Voice Control

Cursor 2.0 includes built-in speech-to-text with custom submit keywords, enabling hands-free coding.

How to Use:

1. Enable voice in settings
2. Press and hold to record
3. Say your code instruction
4. Say "submit" (or custom keyword) to execute

Perfect for accessibility, reviewing code while walking, or when hands are busy.

Spec-Driven Development with Cursor

Cursor's multi-agent architecture pairs perfectly with spec-driven development. Write detailed specifications, let Composer generate a plan, then execute with parallel agents.

Workflow:

1. Create spec.md with requirements
2. Open Composer (Cmd/Ctrl+K): "Read spec.md and create implementation plan"
3. Review the plan, ask Composer to refine
4. "Implement this plan using multiple agents"
5. Composer spawns agents for parallel work
6. Review each agent's output independently

Learn Spec-Driven Development →

Frequently Asked Questions

How much does Cursor cost?

Free tier available with limited usage. Pro plan is $20/month for unlimited Composer access, priority, and advanced features. Business plans available for teams.

Can I use my existing VS Code extensions?

Yes! Cursor is built on VS Code and supports all VS Code extensions. You can import your existing settings and extensions during setup.

What's the difference between Composer and other models?

Composer is Cursor's proprietary model specifically trained for coding (4x faster, <30s responses). You can also use Claude Sonnet 4.5, GPT-5.1 Instant & Thinking (released Nov 12, 2025), or other frontier models through Cursor's model selector for specific use cases.

Do I need to know git worktrees to use multi-agent?

No. Cursor handles git worktrees automatically when running multiple agents. You just review and merge the results like normal git branches.

Does Cursor work offline?

The editor works offline, but AI features require internet connection to access Composer and other models.

Can I use Cursor for commercial projects?

Yes. Pro and Business plans allow commercial use. Always review AI-generated code for security and quality before shipping.

Additional Resources