What you need
Use a 64-bit PC running Windows 10 or newer, including Windows 11, with an internet connection and a Jac Code account. JacCode is installed as a desktop application. You do not need a personal inference API key or an AI-provider configuration.
Free uses JCoder 5.6 Flash only. Paid plans use flagship JCoder 5.6. These model choices are part of Jac Code rather than a list of providers to configure.
Install without opening a terminal
- Open the official JacCode download page and download the Windows EXE installer.
- Run the installer and choose your installation folder. Desktop and Start menu shortcuts are supported.
- Launch Jac Code and sign in or create an account inside the app.
- Start a chat, or open an existing project folder to work with its files.
The optional jac command opens the same graphical application. It is a convenience for terminal users, not a requirement for installation or everyday use. Launch at Windows sign-in can be disabled in Settings.
Make the first request concrete
A useful first request might be: “Explain how this project starts, identify its build and test commands, and show me the files involved.” Begin in Read only if you want to understand a project before changing it.
For a change, describe the expected behaviour, relevant files and a way to check the result. Jac Code can search files, create or patch code, investigate errors and help write and run tests. Use Ask first when you want to approve applicable edits and commands as the work progresses.
A new chat does not require you to choose a project first: the app can create a dedicated workspace for the conversation. Existing project folders can have their own associated chats and saved history.
Bring your local tools and context
Use the development tools installed for your project. Jac Code can inspect setup, use explicit start/build/test command profiles and show source-file changes. Suitable web projects can also show an optional preview.
Supported attachments include code and text, PNG, JPEG, WebP, GIF, PDF, DOCX, XLSX and PPTX. Documented limits include 8 MiB per uploaded file and PDFs of up to four pages. Connect local or remote MCP servers in Settings when you need additional tools, resources or prompts.
Updates and returning to work
The app downloads, verifies and installs updates with visible progress. Signed release information and file hashes authenticate updates. Managed application files are replaced while conversations, projects, settings, attachments and sign-in data are preserved.
For a custom-folder installation, install an upgrade into that same folder. Saved chats and project-associated conversations let you pick up an investigation later. Conversations are distinct from backups of the project's working files.
For help getting started, join the JacCode Discord. For longer multi-step projects, read the agentic coding guide.