Run OpenCode in a sandbox

To run OpenCode in a sandbox on Lizard, connect a credential with lizard agents (a ChatGPT subscription, or an Anthropic, OpenAI, OpenRouter or LLM Gateway key), create a sandbox from the opencode template, and send prompts with lizard sandbox prompt <id> --agent opencode "…". To use OpenCode’s web UI instead, start opencode web --hostname 0.0.0.0 --port 4096 in the sandbox and open the port with lizard sandbox expose.

Test status: the commands come from Lizard CLI 4.0.42 and the platform’s agent runner as of 2026-10-12. We checked the web UI steps against the source of OpenCode 1.18.34, which serves its UI and API from one port, and of Lizard’s sandbox router, which keeps the access token in a cookie and passes WebSockets through. We have not yet run either path end to end in a live sandbox for this page.

Before you start

• Lizard CLI, signed in with lizard login, and a project: run lizard init in a folder, or pass -p <project> to the sandbox commands.
• Lizard Pro or the 7-day Pro trial (card required). Sandboxes bill per second by size while they run; see limits and pricing.

Connect credentials

OpenCode gets every connected credential it accepts to access those providers’ models. It does not take a Claude subscription token; for that, use Claude Code. A ChatGPT login reaches a run as a short-lived access token, never the refresh token. API keys reach a run as environment variables such as ANTHROPIC_API_KEY.

OpenCode names models provider/model. Set a default, or pass -m per prompt:

lizard agents use opencode -m openrouter/anthropic/claude-sonnet-4.5
lizard agents status

With only an OpenRouter key connected and no model chosen, Lizard runs openrouter/openai/gpt-5.3-codex.

Create a sandbox

lizard sandbox create -t opencode --timeout 3600000

Keep the printed ID in a variable: SB=sb_abc123. The CLI default lifetime is five minutes, after which Lizard deletes the sandbox and its files; --timeout 3600000 gives it one hour. The opencode template has Node.js 22, a pinned OpenCode release, git, Python 3, ripgrep, curl, jq, unzip and Lizard CLI.

Copy your code in the same way as for Claude Code:

lizard sandbox exec $SB -- git clone https://github.com/your-org/your-app /workspace/app

For a private or local repository, see put your code in the sandbox.

Send a prompt

lizard sandbox prompt $SB --agent opencode --cwd /workspace/app "add input validation to the signup form"

Each turn runs opencode run --auto, which approves every permission request that is not explicitly denied: OpenCode edits files and runs commands without asking. --effort <level> becomes OpenCode’s --variant. Continue a conversation with -c <conversation-id>, and pass --agent opencode and --cwd again on every follow-up. Ctrl-C stops watching; lizard sandbox interrupt $SB stops the agent.

To get the changes back as a patch, see get the changes back.

Open the OpenCode web UI

opencode web serves OpenCode’s browser interface and its API from one port. Run it in the sandbox and open that port through a preview URL.

Credentials from lizard agents reach only lizard sandbox prompt runs, so this server needs its own key. Copy it in as a file, so it does not appear in a command line:

printf 'export ANTHROPIC_API_KEY=%s\n' "$ANTHROPIC_API_KEY" > opencode.env
lizard sandbox files put $SB opencode.env /root/opencode.env
rm opencode.env

Start the server and open the port:

lizard sandbox exec $SB -- sh -c '. /root/opencode.env && cd /workspace/app && nohup opencode web --hostname 0.0.0.0 --port 4096 >/tmp/opencode.log 2>&1 </dev/null & echo $! > /tmp/opencode.pid'
lizard sandbox expose $SB 4096

Open the URL that expose prints. It carries ?lizard_token=; Lizard moves the token into a cookie for that host and redirects to the same page without it. The cookie authenticates the UI’s requests, event stream and terminal WebSockets.

• You need --hostname 0.0.0.0. OpenCode listens on 127.0.0.1 by default, and the preview URL then answers Sandbox is not listening on port 4096.
• Give a fixed --port. Without one, OpenCode picks a random unused port.
• The URL works like a password: whoever has it can run commands in the sandbox through OpenCode. To require a password as well, add export OPENCODE_SERVER_PASSWORD=… to opencode.env; the user name is opencode.
• Read the server’s log with lizard sandbox exec $SB -- tail -n 50 /tmp/opencode.log. Stop the server with lizard sandbox exec $SB -- sh -c 'kill $(cat /tmp/opencode.pid)'.
• The UI stops when the sandbox stops. Extend it with lizard sandbox timeout $SB 3600000.

Common problems

Related

• Run Claude Code in a sandbox
• Preview URLs
• lizard agents
• lizard sandbox
• Sandboxes

Updated October 12, 2026