OpenCode

Canonical version: OpenCode.

Open-source, provider-agnostic AI coding agent built by the SST team (creators of the SST framework). Runs as a TUI, desktop app, or IDE extension. MIT licensed, written in TypeScript, built with Bun.

Explicitly positioned as an open-source alternative to Claude Code, without provider lock-in. Supports 75+ LLM providers via the Vercel AI SDK.

Key features

• Two primary agents (switch with Tab):
  • build — default, full tool access, makes changes freely
  • plan — read-only analysis, requires approval for edits/bash — good for exploring unfamiliar codebases
• Subagents: general (multi-step research, invoked via @general), explore (read-only codebase exploration)
• LSP integration out of the box (language-aware code understanding, unlike Claude Code)
• Model Context Protocol (MCP) support
• Client/server architecture: TUI is just one frontend; server can be driven remotely
• /init command that analyzes the project and generates an AGENTS.md
• Custom agents defined in opencode.json or markdown files in .opencode/agents/ or ~/.config/opencode/agents/
• Undo/redo, conversation sharing with teams
• Desktop app (beta) for macOS, Windows, Linux

Architecture

• Core: Bun/TypeScript monorepo
• LLM calls: Vercel AI SDK (@ai-sdk/* provider adapters) — what enables 75+ provider support
• Concurrency: Effect (functional TypeScript library)
• TUI: @opentui/core + solid-js (reactive terminal UI)
• DB: Drizzle ORM + SQLite for local session persistence
• HTTP server: Hono
• Parsing: Tree-sitter

Supported providers (sample)

Anthropic, OpenAI, Google (Gemini), Amazon Bedrock, Azure, Groq, Mistral, Cohere, Perplexity, Together AI, xAI (Grok), OpenRouter, Ollama/LM Studio, any OpenAI-compatible API.

Also offers OpenCode Zen (curated model subscription) and OpenCode Go (low-cost open model subscription).

Install

# curl
curl -fsSL https://opencode.ai/install | bash

# npm
npm i -g opencode-ai@latest

# macOS
brew install anomalyco/tap/opencode

# Windows
scoop install opencode

vs Claude Code

References

• Official website: https://opencode.ai
• Documentation: https://opencode.ai/docs
• Source code: https://github.com/sst/opencode

Related

• AI Agent Harness
• Agent Client Protocol (ACP)
• Claude Code
• OpenClaude
• Gemini CLI
• OpenAI Codex
• Kimi Code
• Pi Mono
• Cline
• Goose
• Superset — desktop IDE that drives OpenCode (and other harnesses) in parallel via Git Worktree
• abtop — monitors running OpenCode sessions
• AgentsView — analyzes OpenCode session history and cost
• AI Agents
• AI Agent Skills
• Model Context Protocol (MCP)

About Sébastien

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