OpenCode: The Complete Guide to the Open-Source AI Coding Agent

OpenCode turns AI coding from a disconnected chat into an agent that works directly inside your codebase. Instead of copying snippets back and forth, you’ll learn how to collaborate with an AI coding agent that can read files, run commands, and make real changes while you stay in control. You’ll start with the basics: how OpenCode works, how to reference files, and how to run shell commands to inspect and update a repository. Next, you’ll use slash commands to set context, move faster, and undo changes when needed. You’ll learn the difference between “Plan” mode and “Build” mode to separate thinking from execution, refine your approach, catch edge cases early, and produce cleaner updates before anything is modified. You’ll build safe workflows and learn how OpenCode uses tools with proper permissions. Next, you’ll automate tasks with custom commands, switch between models, enforce formatting, and connect services like GitHub or Slack, configuring OpenCode to match your daily development needs.