> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vibely.sh/llms.txt
> Use this file to discover all available pages before exploring further.
# Plan a change in Plan mode
> Plan mode investigates your project and writes a plan you can review, edit, and approve before any code is written.
**Choose a mode**
The project chat has two modes:
* [**Build mode**](/features/agent/build-mode) (the default) → implement changes, or get an answer when you ask a question
* **Plan mode** → investigate and write a plan you edit and approve before anything is built
Build mode changes the app. Plan mode defines how to build it first. You can switch at any time, and the conversation carries across both.
## Overview
Plan mode turns a change you have in mind into a written plan that you review and approve before any code is written. Vibely investigates your project, reading files, your database schema, and current errors where relevant, then proposes how it would build the change. You read the plan, edit it or ask for revisions, and Vibely builds only what you approve.
Vibely often asks a few clarifying questions before it proposes a plan. When it has a concrete implementation to propose, the plan appears in the project chat and in the **Plan** view.
Plan mode never modifies your code. A Plan mode message is priced by the work it took, the same way as a Build message. See [How Plan mode messages are priced](#how-plan-mode-messages-are-priced).
## What Plan mode is for
Use Plan mode when you know roughly what you want and want to see how Vibely would build it before it does:
* Scope a larger feature and see the files, components, and data it needs
* Investigate a bug and agree on the fix before any code changes
* Compare approaches, understand the tradeoffs, and pick one
* Design a database schema before you build on it
* See which parts of the app a change will touch
* Give collaborators a written plan to review before the build starts
A Plan mode conversation can end without a plan. If you ask a pure question, such as how something works, Vibely answers in the chat instead of writing a plan.
## How to use Plan mode
You can use Plan mode in two ways:
* **Start in Plan mode** when you create a new project or begin a larger feature. The **Plan** toggle is available in the prompt box on the dashboard too.
* **Switch to Plan mode** at any point during development.
### Turn on Plan mode
Click the **Plan** toggle next to the send button. When it's on, the button is highlighted and reads **Plan**. Click it again to go back to Build mode. Then describe the change you want planned.
**Be specific about what you want**
```text wrap theme={"system"}
Add email and password sign-in with password reset. Users should stay signed in for 30 days.
```
**Compare approaches before you commit**
```text wrap theme={"system"}
What's the best way to add real-time notifications to this project? Walk me through the options and their tradeoffs, then plan the one you recommend.
```
**Use it for debugging**
```text wrap theme={"system"}
Users say the login form doesn't work on mobile. Figure out why and plan a fix.
```
**Ask for a detailed breakdown**
```text wrap theme={"system"}
Break down a shopping cart feature. What components, database tables, and API calls will I need?
```
## Review and approve a plan
When Vibely has a plan ready, a plan card appears in the project chat showing the start of the plan, with three actions:
* **Edit**: change the plan text directly in the card.
* **Review**: open the full plan in the **Plan** view, next to the chat.
* **Approve**: accept the plan and start building.
A plan usually includes the goal, the files Vibely will create or change, any dependencies it needs to install, the build order when it matters, and any open questions.
The **Plan** view shows the whole plan as a readable document. From there you can:
* Click **Edit** to rewrite the plan as markdown, then **Save & Approve** to build from your edited version, or **Cancel** to discard your edits
* Click **Approve & Build** to accept the plan as it is
* Close the view and keep talking in the chat
When you approve a plan:
* Vibely switches back to **Build mode**
* The build starts immediately, using the approved plan as its brief
You can turn Plan mode on again at any time to plan the next change against the current state of your project.
### Ask for changes to the plan
While a plan is waiting for approval, the chat input reads **Describe changes you'd like to the plan...**. Type what should change and send it. Vibely revises the plan, and the new version shows what changed: added lines are highlighted and removed lines are struck through.
You can revise a plan up to five times. After the fifth revision, Vibely asks for a final decision: approve the plan as it stands, or send a new message to start a fresh plan.
A plan waits 30 minutes for a decision. If you don't approve it in that time, it expires, and you can send the request again to plan it fresh.
## Plans and persistence
When you approve a plan, Vibely saves it to `.vibely/plan.md` in your project, so you can open it in the [code editor](/features/projects/code-editor) like any other file. Approving a new plan replaces the file with the new plan.
Every plan also stays in your **project chat history**, where you can reopen it from its card.
## How Plan mode messages are priced
A Plan mode message is charged for the AI work it actually took (at least 0.5 credits), whether it ends in a plan, a clarifying question, or an answer. Asking for a revision is a new Plan mode message, priced the same way.
When you approve a plan, Vibely builds it in [Build mode](/features/agent/build-mode). The build is billed as usage-based Build mode work, separately from the planning messages.
## FAQ
No. Vibely only reads your project in Plan mode. Code changes happen after you approve a plan and Vibely switches to Build mode. The one file Vibely writes on approval is the plan itself, at `.vibely/plan.md`.
Yes. Each Plan mode message is charged for the work it took, like a Build message. Building the approved plan is billed separately as Build mode work.
The latest approved plan is saved to `.vibely/plan.md`. Earlier plans stay in the project chat history.
Yes. Click **Edit** on the plan card or in the Plan view, change the text, and click **Save & Approve**. Vibely builds from your edited version.
Your project's files, your database schema, errors from your running preview, the web, your [skills](/features/context/skills), and connected MCP servers. For larger investigations, it can send read-only [subagents](/features/agent/subagents) to research parts of the project in parallel.
Yes. Plan mode is well suited to investigating an issue and agreeing on a fix before any code changes.
Yes. For a large or ambiguous request sent in Build mode, Vibely may stop before writing code and present a plan for your approval first.
## Related topics
Implement changes and ask questions.
How Vibely investigates larger tasks.
Everything you can do in the project chat.
How credits are counted.
## Related topics
- [Implement changes in Build mode](/features/agent/build-mode.md)
- [FAQ](/faq.md)
- [Iterate](/features/web-apps/iterate.md)
- [Prompting](/prompting/best-practices.md)
- [Subagents](/features/agent/subagents.md)
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