opencode-chromium

OpenCode Browser Plugin

Your browser, connected to your coding agent.
Four compact tools. Local action memory. Optional decision assistance.

Get started

Install the matching browser extension, then connect all detected supported harnesses and native hosts:

npx -y opencode-chromium@latest setup --all

Setup shows what changed and keeps transactional backups. Preview with --dry-run --json. Quit and reopen desktop harnesses, or reconnect MCP in terminal clients. For Firefox and LibreWolf, complete the guided loopback setup. The AMO install button becomes available after Mozilla approves the initial submission.

Codex CLI and Codex Desktop

npx -y opencode-chromium@latest setup --targets codex

Both use the shared Codex MCP configuration. Codex guide.

Claude Code

npx -y opencode-chromium@latest setup --targets claude-code

Claude Desktop

npx -y opencode-chromium@latest setup --targets claude-desktop

Supported setup targets: Windows and macOS.

OpenCode

npx -y opencode-chromium@latest setup --targets opencode

Uses the native adapter by default and the detected version's configuration format. OpenCode guide.

DeepSeek Harness

npx -y opencode-chromium@latest setup --targets dsh

Registers MCP in the Cordis profile patch. Harness guide.

Generic MCP client

Add this stdio server to your client's MCP configuration:

{
  "mcpServers": {
    "browser": {
      "command": "npx",
      "args": ["-y", "opencode-chromium@latest", "mcp"]
    }
  }
}

Full MCP guide.

JavaScript SDK

npm install opencode-chromium

import { createBrowserAgent } from "opencode-chromium/sdk";

SDK examples and lifecycle.

Choose your browser

Browser family	Connection	Setup
Chrome, Edge, Brave, Chromium	Chromium extension and CDP	Store extension + native host
Firefox, LibreWolf	Firefox extension and WebDriver BiDi	Signed add-on + native host + guided loopback setup

Desktop discovery covers Windows, macOS, and Linux. Firefox requires version 140 or later; LibreWolf must expose the matching Remote Agent. Compatible derivatives need individual validation; this does not claim support for every fork. See Firefox capabilities and compatibility for transport differences and verification limits.

Named profiles choose the browser. Agents keep the same four tools: browser_run, browser_observe, browser_session, and browser_finalize. Sessions own their tabs, targets are checked against the live page, and uploads require confirmation by default. Profiles · Security.

A calmer operating panel

Overview brings connection health, decision assistance, and memory together. Profiles selects the browser connection. Settings holds uploads, memory retention, and advanced controls. Detailed usage and timings expand when you need them, with automatic light and dark themes.

Cloud assistance is off by default. Choose Jev through OpenRouter or TypeSafe, or OpenAI Luna through OpenRouter. Luna can rank ambiguous visual targets using one bounded screenshot when you separately opt in. Exact matches stay local; timeouts and abstentions retain local results. Decision assistance guide · Local action memory.

npm downloads

The scheduled chart workflow refreshes these assets. npm download counts are package downloads, not unique users or extension installs.

Manage, update, and troubleshoot

npx -y opencode-chromium@latest setup --all --dry-run --json
npx -y opencode-chromium@latest setup --targets codex,opencode
npx -y opencode-chromium@latest manage
npx -y opencode-chromium@latest doctor --json
npx -y opencode-chromium@latest status --json
npx -y opencode-chromium@latest uninstall --targets codex

Use --config harness-id=/absolute/path for a custom configuration. Existing aliases, package names, profiles, and runtime data remain supported. Runtime linking · Troubleshooting.

Develop and release

bun install --frozen-lockfile --ignore-scripts
bun run build
bun run build:extension
bun run build:extension:firefox
bun run check
bun run check:firefox

Both extensions share WXT/React source. Separate output directories prevent one build replacing the other. Forward version bumps on master trigger npm and store release workflows. Mozilla submissions can remain pending review before publication. Architecture · Firefox publishing.

Questions and ideas: Discussions. Bugs: Issues. MIT license.