Cursor 2.0 Deep Dive: Custom Model, Multi-Agent, Plan Mode & Security Concerns (2025 Latest)

Cursor in 2025 has undergone its most significant upgrade yet—Cursor 2.0. This update isn't just feature enhancement, it's a paradigm shift:

From AI-assisted coding → AI-driven / Multi-Agent collaborative coding in an AI-Native IDE.

This article provides a systematic analysis from five perspectives: feature updates, technical breakthroughs, security risks, competitive landscape, and real implications for developers.

🆕 1. Major Updates & Latest Developments in Cursor (2025)

⭐ 1.1 Cursor 2.0 Launch + Custom Model Composer

The biggest highlight of Cursor 2.0 is the introduction of the proprietary coding model Composer.

Composer's Key Features:

Specifically trained for coding tasks
~4× faster inference than comparable models
Most coding-related turns (generation/completion/refactoring) take only ~30 seconds
More stable performance on long-context projects
Better suited for multi-agent collaboration

The industry widely views Composer as a crucial step in building Cursor's moat: transitioning from "relying on external large models" to "having its own native coding model."

⭐ 1.2 Multi-Agent Interface: Up to 8 Agents Working in Parallel

Cursor 2.0 allows you in a single prompt to:

Launch up to 8 AI agents
Each agent executes in an isolated environment (git worktree/remote)
Each agent generates independent implementation solutions
Final aggregated diff for unified comparison and merging

This is equivalent to: "Having an AI team of 8 senior programmers working in parallel to implement the same requirement."

Use Cases:

Large-scale refactoring
Cross-file tasks
New feature solution comparison
UI/API multi-version experimentation
Performance/architecture optimization

⭐ 1.3 New Plan Mode

Plan Mode is the intelligent soul of Cursor 2.0.

Before executing complex tasks, the agent will:

Analyze the entire codebase
Break down the task
Auto-generate a step-by-step plan
Execute according to the plan

This solves the most common problems AI faces in large projects:

❌ Not knowing which files to modify
❌ Going in the wrong direction halfway through
❌ Discontinuous/destructive changes
❌ Errors in cross-file relationships

Plan Mode = Improved reliability for complex tasks.

⭐ 1.4 Built-in Browser + DOM Tools (Major Enhancement for Frontend Projects)

Now Cursor's agent can:

View UI
Manipulate DOM
Understand frontend structure
Modify frontend code and verify on-site

For frontend developers, this is transformative:

✅ More accurate CSS, DOM, and component tree analysis
✅ Automated UI debugging
✅ UI testing execution
✅ Agent can directly observe pages and make modifications

⭐ 1.5 Core Trends Summary

Cursor is completing a leap from IDE → AI-native:

✔ Custom model
✔ Multi-agent parallelism
✔ Plan-based execution (Plan Mode)
✔ UI-manipulable browser tools
✔ Continuously enhanced project-level refactoring capabilities

This marks Cursor as not just "AI that writes code," but an autonomous coding agent system.

⚠️ 2. Critical Issues & Controversies

AI IDEs are evolving rapidly, but their risks are expanding equally fast.

❗ 2.1 Security/Vulnerability Risks: AI Agents = New Attack Surface

Recent security research indicates:

When you open a "malicious repository," AI agents executing code with high privileges:

Can be tricked into executing malicious commands
Including reading sensitive files, running scripts, writing to critical directories, etc.

Reasons include:

Agents often have permissions to write files, execute tests, call CLI
Users are often unaware
AI can be deceived by prompt injection
Long execution chains, high automation level

A vulnerability in Cursor was disclosed in 2025:

🔥 CVE-2025-59944

Case-sensitivity bug in filename handling
Could allow attackers to bypass protection mechanisms
Could modify critical configuration files

Conclusion: AI agent automation + permission system = new IDE attack patterns.

❗ 2.2 Does Cursor Have a "Defensible Moat"? Under Scrutiny

The industry article "Does Cursor Have a Defensible Moat?" raises concerns:

IDE market competition is extremely fierce
Big tech companies may launch stronger AI IDEs (Google/Microsoft/JetBrains)
Model layer substitutability is high
Integrated DevOps products may capture market share

Industry Opinion:

Cursor is strong, but must continue rapid iteration, otherwise advantages will be hard to maintain.

❗ 2.3 Intensifying Competition: Cursor Isn't the Only AI IDE

Other vendors are launching similar or more aggressive coding agent tools:

Web IDE + Agent
CLI-first dev agent IDEs
Cloud-based fully automated coding agents
Browser IDEs directly replacing traditional IDEs
Code generation tools with physical executors

Cursor is no longer the "only AI IDE".

💡 3. Real Implications for Developers

Leap in Development Efficiency

Cursor 2.0's multi-agent mode combined with Plan Mode can:

Reduce large refactoring task time by 60-80%
Minimize human errors in cross-file editing
Provide multiple implementation solutions for comparison

Lowered Learning Curve

By observing AI agent's Plan and execution process, junior developers can:

Understand architectural thinking in large projects
Learn best practices and code patterns
Quickly adapt to new tech stacks

New Workflow

Shift from traditional "write code → test → debug" to:

Describe requirements and constraints
Review AI-generated Plan
Supervise agent execution
Validate and fine-tune results

🎯 4. How to Maximize Cursor 2.0

Best Practices

Clear requirement descriptions: Provide sufficient context and constraints
Leverage Plan Mode: Let AI create plans for complex tasks first
Use multi-agent: For critical features, enable multiple agents to generate different solutions
Security awareness: Don't blindly enable all permissions on projects with sensitive information

Suitable Scenarios

✅ Large project refactoring
✅ Cross-file feature implementation
✅ Frontend UI rapid iteration
✅ API development and testing
✅ Code quality optimization

Unsuitable Scenarios

❌ Highly customized low-level systems
❌ Scenarios requiring deep algorithm optimization
❌ Production environments with sensitive data
❌ Situations requiring precise control over every line of code

📊 5. Competitive Comparison

Cursor vs GitHub Copilot

Cursor: Complete IDE experience, multi-agent collaboration, stronger autonomous capabilities
Copilot: Lighter weight, better integration, but weaker autonomy

Cursor vs Windsurf

Cursor: Custom model, multi-agent parallelism, more mature ecosystem
Windsurf: Smoother Flow mode experience, but slightly behind in overall features

Cursor vs JetBrains AI

Cursor: Independent IDE, AI-first design
JetBrains AI: AI enhancement of traditional IDE, suitable for heavy JetBrains users

🔮 6. Future Outlook

Technology Trends

Stronger autonomy: From assistance tools to true "AI colleagues"
Better security mechanisms: Sandbox environments, permission granularity, audit logs
Deeper project understanding: Understanding business logic and architectural patterns

Potential Development Directions

Team collaboration mode: Multi-person + multi-agent coordinated work
Cloud integration: Deep integration with CI/CD and testing platforms
Domain specialization: Optimized versions for specific languages or frameworks
On-premise deployment: Enterprise-grade private deployment solutions

✅ Conclusion

Cursor 2.0 represents a new phase for AI IDEs:

Core Value:

✅ Custom model provides faster, more accurate coding experience
✅ Multi-agent parallelism makes complex tasks manageable
✅ Plan Mode improves AI reliability in large projects
✅ Browser tools transform frontend development experience

Cautions:

⚠️ Security risks cannot be ignored
⚠️ Competitive pressure continues to increase
⚠️ Moat needs continuous construction

For developers, Cursor 2.0 isn't just a tool upgrade—it's a revolution in work methodology. Leveraging its capabilities wisely while maintaining security awareness will help you stay competitive in the AI era.

Have you used Cursor 2.0? How have Multi-Agent and Plan Mode changed your workflow? Share your experience in the comments.