OpenCode
An open-source coding agent with terminal build and read-oriented plan modes, a general subagent and an optional beta desktop app.

Overview
An open-source coding agent with terminal build and read-oriented plan modes, a general subagent and an optional beta desktop app.
Terminal coding-agent workflow with build and read-oriented plan modes · General subagent for complex search and multistep work · Beta desktop app for macOS, Windows and Linux
Coding agents & IDEs · MIT
Original source & installation instructions
The desktop app is beta, and the build agent has broad access; review command permissions. MIT code does not include model/provider service rights or costs.