Welcome
Happy Desktop is the open source harness for coding agents. It runs Claude, Codex, and Grok on the subscriptions you already have, on your own machine, with one permission model, durable sessions, and an end-to-end encrypted phone app.
Download it for macOS, Windows, or Linux and open it. Happy starts its own agent runtime and picks up the Claude, Codex, and Grok sign-ins on the machine.
What you get
- Every model, native. Claude gets Claude Code's prompts and tools, GPT models get Codex's, Grok gets Grok Build's. Switch mid-session; the transcript stays.
- Your subscriptions. No Happy account for model access. Credentials come from the Claude Code, Codex, and Grok CLI sign-ins already on the machine.
- Chief of Staff. A built-in agent that configures your setup in conversation: imports projects, pairs your phone, deploys a remote agent, creates a team, upgrades Happy.
- Durable sessions. Every conversation and subagent survives a closed window and a restart, and takes the next message with full context.
- Auto mode. Reads and workspace edits run freely. Everything else is sandboxed by the OS. The few actions that cross the boundary are reviewed automatically, never by prompting you.
- Workspaces. Parallel work gets its own Git worktree on its own branch.
- Phone. The same sessions, end-to-end encrypted. The relay carries ciphertext only.
- Multiplayer. Invite someone into a session, or run one Happy Agent for a team.
- Skills, MCP. Markdown files and TOML entries. An agent can write both.
- MIT. Read it, fork it, ship your own build.