OpenCode — Open-Source AI Coding Agent for Terminal

What it is

OpenCode is an open-source AI coding agent designed for terminal-first workflows. It features a TUI (terminal user interface) for interactive coding sessions, LSP (Language Server Protocol) integration for code intelligence, and support for multiple LLM providers including OpenAI, Anthropic, and local models. The project provides a free alternative to commercial terminal coding agents.

Developers who prefer working in the terminal and want an AI coding assistant that integrates with their existing command-line workflow benefit most. OpenCode brings code understanding, generation, and review capabilities without leaving the terminal.

How it saves time or tokens

OpenCode's LSP integration provides the AI with type information, definitions, and references from your project without sending entire files into context. This targeted context injection reduces token usage while improving code suggestion accuracy. The TUI provides a persistent session with history, so you avoid re-explaining context across separate prompts. Multi-provider support lets you choose the most cost-effective model for each task.

How to use

1. Install OpenCode:

# Via Go
go install github.com/opencode-ai/opencode@latest

# Or download binary from releases
curl -sSL https://github.com/opencode-ai/opencode/releases/latest/download/opencode-linux-amd64 -o opencode
chmod +x opencode

1. Configure your LLM provider:

export OPENAI_API_KEY='sk-...'
# Or
export ANTHROPIC_API_KEY='sk-ant-...'

1. Start an interactive session in your project directory:

cd my-project
opencode

The TUI launches with your project context loaded. Start asking questions or requesting code changes.

Example

# Non-interactive mode for one-shot tasks
opencode 'Add error handling to all HTTP handlers in cmd/api/'

# Review a specific file
opencode 'Review src/auth/jwt.go for security issues'

# Generate tests
opencode 'Write table-driven tests for the ParseConfig function in config.go'

# Interactive TUI session
opencode
> /diff   # Show pending changes
> /apply  # Apply suggested changes
> /undo   # Revert last change

Related on TokRepo

• AI Coding Tools -- Terminal coding agents and developer tools
• Automation Tools -- Workflow automation for developers

Common pitfalls

• OpenCode requires an LLM API key. Without one, the agent cannot function. Local model support (Ollama) is available but requires separate setup.
• LSP integration depends on having the appropriate language server installed (gopls for Go, typescript-language-server for TypeScript, etc.). Without it, OpenCode falls back to file-based context.
• The TUI uses terminal features that may not render correctly in all terminal emulators. Use modern terminals (iTerm2, Alacritty, WezTerm) for the best experience.