How to start building an app with Cursor

To start building an app with Cursor, open a dedicated project folder, explain the first useful outcome and ask for a plan before a substantial implementation. Then choose one bounded feature, review the changes and run a check that demonstrates the feature works.

If you are a founder struggling to find the “right prompt,” start by making the project easier to understand. A prompt needs enough context to guide a choice, not a long list of everything the app might eventually become.

Begin with a clear first version

Write down the user, the result they need and one journey that delivers it. A fictional event checklist app could begin with creating an event, adding tasks and marking those tasks complete. Ticket sales, team accounts and automated reminders can remain later possibilities.

Decide what must be saved and what should survive reopening the app. If several people share information, identify their access rules. You can leave minor visual details open while agreeing on these foundation choices.

Use the MVP scope guide if the first version is still too broad.

Open the project and check the workspace

Follow Cursor's official quickstart for installation and sign-in. Open the folder you intend to work in and use Agent for the implementation conversation. The quickstart also covers reviewing changes and using Plan Mode for larger tasks.

For an empty folder, explain that no application exists yet. For an existing folder, ask Cursor to describe its current structure and working behaviour before making changes. Do not request a fresh setup over an existing project without understanding what would be replaced.

Give the tool access only to the workspace it needs. Keep a recoverable copy or version-control checkpoint before consequential changes. Account access, available models and usage limits should be checked in Cursor's current product settings.

Use a first prompt that explains the outcome

I am planning an event checklist app for one organiser.
The first version needs events, tasks and completion status.
An event and its tasks should remain available after reopening.

Accounts, ticket sales and automatic reminders are outside
the first version. I need advice on an appropriate setup.

Inspect this folder first. Summarise what already exists.
Then propose the smallest suitable first milestone and
explain how we can check it. Do not edit files yet.

This fictional example leaves room for a recommendation while protecting the scope. Adapt it to your own users, data and operating environment. A project with shared private information will need a different access model from a checklist you use yourself.

Review the plan before asking Cursor to build

Check whether the proposed plan:

• Preserves your explicit requirements.
• Separates recommended choices from choices you already made.
• Includes the storage and access behaviour the journey needs.
• Avoids features you explicitly deferred.
• Provides a result you can demonstrate.

Ask for an explanation of consequential decisions in familiar terms. For example, if the recommendation introduces a hosted database, ask why local storage is unsuitable and what operational responsibility the service adds.

Cursor can help with planning itself. PenguinKit is an optional way to prepare a separate, organised foundation; it is not required to use Cursor and does not replace examining Cursor's implementation.

Give the agent one implementation task

Once you accept the approach, request the first useful milestone:

Implement the agreed event-and-task milestone only.
Use the approved storage approach.

Check that I can create an event, add a task, mark it
complete and reopen the app without losing that state.
Reject a blank task name without creating a partial task.

Do not add deferred features or replace unrelated files.
Report the changes, checks that ran and remaining limits.

A milestone should cover a coherent action rather than a large number of screens. If the project needs authentication, its first milestone may instead demonstrate one protected journey with the correct access checks.

Keep project guidance easy to find

Keep the overview, scope and decisions in named project files. Tell Agent which ones to read. If you need repeated guidance, Cursor documents project rules in .cursor/rules and an AGENTS.md alternative in its rules guide.

Do not copy a large collection of generic rules into every small project. Start with the actual constraints, the relevant conventions and the checks your project uses. Refer to authoritative files rather than maintaining conflicting copies of requirements.

Review that guidance when the project changes. A rule based on an old storage decision can become misleading even if it was useful earlier.

Check the result before adding more features

Open the app and try the agreed journey. Examine the changed files and ask the agent to run the available checks. If a check could not run, record it as unverified rather than treating a confident explanation as evidence.

Use the first-milestone testing guide to include a meaningful boundary and invalid input. Keep production connections separate from experiments until the relevant provider behaviour has been checked.

If the tool starts expanding scope, return to the agreed milestone and update the plan deliberately. A clearer project record is often a better next step than another increasingly long prompt.

Start with PenguinKit when you want help shaping the idea, discussing major decisions and preparing a foundation to take into Cursor. The implementation and its verification happen in your chosen development workflow.