====== OpenCode ======

**OpenCode** is an open-source, terminal-native AI coding agent that provides intelligent code generation, refactoring, debugging, and documentation assistance. With over **129,000 GitHub stars** and 800+ contributors, it has become one of the most popular open-source alternatives to proprietary coding assistants.

| **Repository** | [[https://github.com/anomalyco/opencode|github.com/anomalyco/opencode]] |
| **License** | MIT |
| **Language** | Go, TypeScript |
| **Stars** | 129K+ |
| **Category** | AI Coding Agent |

===== Key Features =====

  * **Multi-Provider Support** -- Connects to 75+ LLMs via Models.dev including OpenAI GPT-4, Anthropic Claude, Google Gemini, and local models via Ollama/LM Studio
  * **Terminal-Native TUI** -- Beautiful terminal user interface optimized for power users with session management and real-time feedback
  * **LSP Integration** -- Auto-loads Language Server Protocol servers (PyRight, Rust Analyzer, TypeScript) for real-time code feedback
  * **MCP Support** -- Model Context Protocol servers for extended context such as GitHub repository access
  * **Plan and Build Modes** -- Plan mode for analysis/explanation, Build mode for code changes and edits
  * **Multi-Session** -- Run parallel agents on the same project with shareable session links
  * **GitHub Integration** -- Trigger via /opencode comments in issues and PRs, executing in GitHub Actions runners
  * **Offline Mode** -- Full functionality with local models at zero API cost

===== Architecture =====

OpenCode operates as a modular, provider-agnostic system with several key components:

  * **Core Agent Engine** -- Handles natural language processing via connected LLMs with context management
  * **LSP Integration Layer** -- Auto-discovers and loads language-specific servers for real-time code feedback, improving LLM accuracy
  * **MCP Client** -- Optional remote or local MCP servers for extended context
  * **ACP Support** -- Agent Client Protocol for standardized editor/IDE communication
  * **TUI Renderer** -- Terminal user interface with interactive chat, session management, and visualization

<mermaid>
graph TB
    subgraph UI["Terminal UI"]
        TUI[TUI Renderer]
        Chat[Interactive Chat]
        Sessions[Session Manager]
    end
    subgraph Agent["Agent Core"]
        Engine[Agent Engine]
        Plan[Plan Mode]
        Build[Build Mode]
    end
    subgraph Providers["LLM Providers"]
        Cloud[Cloud APIs - GPT-4 / Claude / Gemini]
        Local[Local Models - Ollama / LM Studio]
    end
    subgraph Tools["Tool Layer"]
        LSP[LSP Servers]
        MCP[MCP Servers]
        Git[Git Integration]
        FS[Filesystem Tools]
    end
    UI --> Agent
    Agent --> Providers
    Agent --> Tools
    LSP --> Engine
</mermaid>

===== Supported Providers =====

OpenCode is model-agnostic, connecting to providers via Models.dev:

  * **Cloud Providers** -- OpenAI (GPT-4, 8K-200K context), Anthropic (Claude Opus/Sonnet), Google (Gemini)
  * **Local/Free** -- Code Llama, DeepSeek Coder, StarCoder via Ollama or LM Studio
  * **Subscriptions** -- Direct login for ChatGPT Plus/Pro, GitHub Copilot

Performance scales with model quality: GPT-4/Claude achieves 80-90% quality vs commercial tools; open models reach 60-70%.

===== Code Example =====

<code python>
# AGENTS.md configuration example for OpenCode
# Place in your project root to provide context to the agent
#
# Project: MyApp
# Tech Stack: Python 3.12, FastAPI, PostgreSQL
# Testing: pytest with coverage
# Conventions: type hints, PEP 8, docstrings required
#
# Usage:
#   pip install opencode
#   opencode                              # launches TUI
#   opencode "refactor to async/await"    # direct command

import subprocess
import json

def run_opencode_headless(prompt, model="claude-sonnet"):
    result = subprocess.run(
        ["opencode", "--headless", "--model", model, prompt],
        capture_output=True, text=True
    )
    return json.loads(result.stdout)

output = run_opencode_headless("Add error handling to api/routes.py")
print(output["changes"])
</code>

===== References =====

  * [[https://github.com/anomalyco/opencode|OpenCode GitHub Repository]]
  * [[https://opencode.ai|OpenCode Official Website]]
  * [[https://opencode.ai/docs/github/|OpenCode GitHub Integration Docs]]

===== See Also =====

  * [[dify|Dify]] -- Agentic workflow platform
  * [[mcp_servers|MCP Servers]] -- Model Context Protocol implementations
  * [[langfuse|Langfuse]] -- LLM observability for monitoring agent performance