Describe the app with Brew

Choose Brew Juice and explain the task, who will use the app, and what the result should be. Include example inputs and any constraints, such as keeping records on this computer.

Brew asks questions and prepares an app plan. Review that plan before building. Clarify which features belong in the first version and whether you need an Agent conversation, a specific AI action, or both.

Brew product-planning example, captured for the August 2026 Guide.

Choose a starting point

Blank Starter provides a minimal app foundation. Agent Starter includes a shared Agent conversation and example interactions between the Agent and app content. These are starting points that Builder can adapt, rather than finished apps for a particular job.

Choose the Agent starting point when conversation is part of the intended first version. A simple form or fixed action may fit Blank Starter.

To build an assistant into your app, see the ready-made Agent Conversation component. The same chapter covers a compact Chat Widget and specific AI actions such as summarizing or transcribing.

Improve an app in Tweak

Open the app in Tweak and describe the change with an example: “Add a date filter to this list, and keep the existing export format.” The running app and Builder conversation stay together so you can review the result in context.

  1. Explain what should change and what must stay the same.
  2. Review any plan or access request that affects the work.
  3. Try the changed workflow using representative input.
  4. Return to Use when the result is ready.

Work with Builder

Attach relevant files or selected text to explain the problem. The model and Thinking controls select the available model and its reasoning setting; options depend on the provider.

During a task, Steer gives new guidance to the active work. A Follow-up queues another request. Stop interrupts current work; it does not undo changes already made. Check the app and the conversation before continuing.

Adjust your building workspace

Open Settings → Building. Start with Standard mode for everyday app building. Tech Guru shows additional technical controls for people comfortable with development tools.

Choose whether the Builder panel appears on the left or right. Enable completion notifications if you want to know when Builder finishes while its workspace is in the background.

Building settings control the level of technical detail, notifications, and panel placement. AppJuice 0.351.0 Preview, local browser view, September 14, 2026.

Add Building Skills

A Skill is a set of instructions for a kind of work. AppJuice includes skills for app structure, Agent and AI integration, host capabilities, experience checks, and publishing.

Built in
AppJuice supplies and maintains these instructions for Builder.
Global
Install extra Building Skills in Settings when they should be available across apps.
App only
Use the Skills controls in Tweak for instructions needed by this app.

Building Skills guide changes to the app. Runtime Agent Skills guide the assistant when someone uses the app. Installing a Building Skill does not automatically enable it for an app's Runtime Agent.

Review and restore Snapshots

Snapshots record versions of app source. Open Snapshots to inspect saved changes and choose a source version to restore when needed.

A source snapshot is not a backup of every business record, uploaded file, or external service. Review the restore action and back up data separately before a change that may alter its format.

Use advanced development tools

Tech Guru mode exposes an embedded coding terminal and additional development controls. External coding tools can also work on an app workspace. These paths assume familiarity with source files and commands.

For adding platform capabilities in code, use the advanced Agent and AI API reference. Most users can describe the desired change to Builder instead.