> ## Documentation Index
> Fetch the complete documentation index at: https://docs.replit.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Plan vs. Build Mode
> Learn the difference between Plan and Build modes in Replit, and how to combine them for more effective development.
Replit Agent offers two interaction modes: **Plan Mode** and **Build Mode**. Use them together to think through your ideas first, then implement with confidence.
## What is Plan Mode?
[Plan Mode](/core-concepts/agent/plan-mode) lets you brainstorm, ask questions, and plan your work with Agent—without modifying any code. Think of it as a collaborative planning session where you can explore ideas freely.
Plan Mode is perfect for:
* **Brainstorming ideas**: Explore different approaches before committing to one
* **Breaking down complex projects**: Get a structured task list before building
* **Learning and understanding**: Ask questions about technologies, patterns, or your codebase
* **Planning architecture**: Design your app's structure before writing code
In Plan Mode, Agent reads your project and provides guidance, but it won't make any changes to your files. When you're ready to implement, switch to Build Mode or approve a plan to start building automatically.
## What is Build Mode?
Build Mode is the default mode where Agent writes code, modifies files, and implements features directly in your project. This is where ideas become reality.
Use Build Mode when you're ready to:
* **Create new features**: Let Agent write the code for your next feature
* **Set up your app**: Install dependencies, configure databases, and connect services
* **Fix issues**: Let Agent debug and resolve problems in your codebase
* **Refactor code**: Improve existing code structure and organization
## Using both modes together
**Plan Mode and Build Mode work best as a sequence.** Start by planning to clarify your thinking, then build with a clear direction.
Switch to Plan Mode and describe what you want to build. Agent will help you think through the requirements, suggest approaches, and identify potential challenges—all without touching your code.
Ask Agent to create a development plan. It will break down your project into specific, actionable tasks with clear priorities and dependencies.
Review the proposed plan. Ask follow-up questions, request changes, or explore alternative approaches. Keep iterating until the plan matches your vision.
When you're satisfied with the plan, select **Start building**. Agent automatically switches to Build Mode and begins implementing the approved tasks.
Monitor Agent's progress as it works through the task list. Each completed task creates a checkpoint, so you can review changes and roll back if needed.
## When to use each mode
* You're starting a new project and need direction
* You want to explore different approaches
* The task is complex and needs breaking down
* You want to learn before implementing
* You're unsure about the best solution
* You know exactly what you want
* You have a clear plan ready to execute
* You're making quick fixes or small changes
* You're following an approved task list
* Speed of implementation is the priority
**Not sure which to pick?** If your request involves multiple features or significant changes, start with Plan Mode. For simple, well-defined tasks, go straight to Build Mode.
## Key differences
| Feature | Plan Mode | Build Mode |
| ---------------- | -------------------------------- | ------------------------------ |
| **Purpose** | Brainstorm, plan, and learn | Implement and build |
| **Code changes** | None—read-only | Writes and modifies files |
| **Output** | Ideas, task lists, guidance | Working code and features |
| **Best for** | Complex projects, exploration | Clear tasks, implementation |
| **Transition** | Click "Start building" to switch | Already in implementation mode |
## Best practices
### Getting the most from Plan Mode
* **Be specific about requirements**: The more detail you provide, the better the plan
* **Ask follow-up questions**: Clarify suggestions you don't understand
* **Request examples**: Ask Agent to show code snippets or patterns
* **Discuss trade-offs**: Explore pros and cons of different approaches
* **Iterate on ideas**: Refine the plan until it feels right
### Seamless transitions
* **Review before building**: Always review the task list before approving
* **Start small**: Begin with a subset of tasks if the full plan feels overwhelming
* **Use checkpoints**: Agent creates checkpoints as it builds, so you can always roll back
## Next steps
Deep dive into planning features
Explore all Agent capabilities
Learn about rollbacks and recovery
Write better prompts for Agent