How to use OpenCode: install, plan and build, MCP

To use OpenCode, install it, connect a model provider with /connect, run /init to create an AGENTS.md, and switch between the Plan and Build agents with Tab. Undo anything you don’t like with /undo, and add MCP servers in opencode.json to give it tools beyond your repository.

OpenCode is an open-source coding agent for the terminal. The steps below follow OpenCode’s documentation.

1. Install OpenCode

The install script is the quickest route:

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

It is also on npm (npm install -g opencode-ai) and Homebrew (brew install anomalyco/tap/opencode), with Chocolatey, Scoop and Docker options for Windows.

2. Connect a model provider

Start OpenCode in your project:

cd ~/code/my-app
opencode

Then run /connect in the interface, pick the provider, sign in and paste the API key it gives you.

3. Create an AGENTS.md

/init

/init analyses your project and creates an AGENTS.md in the project root. Read it, cut anything vague, add the commands to build and test, and commit it: OpenCode’s docs recommend checking it into Git so everyone on the project shares it.

4. Plan first, then build

OpenCode has two primary agents, and Tab switches between them:

• Plan blocks changes and suggests how to implement what you asked.
• Build makes the changes.

For anything bigger than a small fix, start in Plan, read and correct the plan, then press Tab and let Build do it.

5. Undo and redo

/undo reverts the most recent changes and restores the prompt that caused them, so you can rephrase and try again. Run it several times to step further back. /redo puts an undone change back.

6. Add MCP servers

OpenCode reads MCP servers from the mcp object in opencode.json. A remote server needs its url:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "polylane": {
      "type": "remote",
      "url": "https://mcp.polylane.com/mcp",
      "enabled": true
    }
  }
}

A local server gives the command as an array, with any environment it needs:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "context7": {
      "type": "local",
      "command": ["npx", "-y", "@upstash/context7-mcp"],
      "enabled": true
    }
  }
}

For a remote server that needs sign-in, OpenCode starts the OAuth flow when the server answers with a 401, using dynamic client registration when the server supports it. opencode mcp list shows your servers, and opencode mcp auth <name> runs the sign-in by hand.

The remote server in the first example is Polylane’s. It brings production into OpenCode: logs, traces and deploys from every provider you connect, behind one sign-in.

Using OpenCode? See how to give OpenCode production context with Polylane.