> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/anomalyco/opencode/llms.txt
> Use this file to discover all available pages before exploring further.

# web

> Start OpenCode server with web interface

## Overview

The `web` command starts an HTTP server and automatically opens a web browser to access OpenCode through a web interface. This provides:

* Browser-based UI for OpenCode
* Access from any device on your network
* Shareable link for team collaboration
* Same functionality as the TUI

## Usage

```bash theme={null}
opencode web
```

The command will:

1. Start the OpenCode server
2. Display local and network access URLs
3. Automatically open your default browser

## Options

<ParamField path="--port" type="number" default="0">
  Port to listen on. Default is `0` (random available port).
</ParamField>

<ParamField path="--hostname" type="string" default="127.0.0.1">
  Hostname to listen on. Use `0.0.0.0` to allow external connections.
</ParamField>

<ParamField path="--mdns" type="boolean" default="false">
  Enable mDNS service discovery. When enabled, defaults hostname to `0.0.0.0`.
</ParamField>

<ParamField path="--mdns-domain" type="string" default="opencode.local">
  Custom domain name for mDNS service.
</ParamField>

<ParamField path="--cors" type="string[]" default="[]">
  Additional browser origins to allow for CORS. Can be specified multiple times.
</ParamField>

## Examples

### Local Access Only

Start web interface on localhost:

```bash theme={null}
opencode web
```

Output:

```
  Local access:      http://localhost:3456
```

### Network-Wide Access

Allow connections from other devices on your network:

```bash theme={null}
opencode web --hostname 0.0.0.0 --port 4096
```

Output:

```
  Local access:      http://localhost:4096
  Network access:    http://192.168.1.100:4096
```

Share the network URL with teammates to collaborate.

### With mDNS Discovery

Make the server discoverable via mDNS:

```bash theme={null}
opencode web --mdns
```

Output:

```
  Local access:      http://localhost:3456
  Network access:    http://192.168.1.100:3456
  mDNS:              opencode.local:3456
```

### Custom Domain and Port

```bash theme={null}
opencode web --mdns --mdns-domain myproject.local --port 8080
```

## Authentication

<Warning>
  When exposing the web interface to your network, always enable authentication to prevent unauthorized access.
</Warning>

Enable HTTP basic authentication:

```bash theme={null}
export OPENCODE_SERVER_PASSWORD="your-secure-password"
opencode web --hostname 0.0.0.0
```

The browser will prompt for credentials:

* **Username**: `opencode` (or set `OPENCODE_SERVER_USERNAME`)
* **Password**: Value of `OPENCODE_SERVER_PASSWORD`

## Network Access Patterns

When you start with `--hostname 0.0.0.0`, OpenCode displays multiple access URLs:

### Local Access

Use `http://localhost:<port>` from the same machine.

### Network Access

OpenCode automatically detects your local network IPs (excluding Docker bridges and IPv6). Share these URLs with others on your network:

```
Network access:    http://192.168.1.100:4096
Network access:    http://10.0.0.50:4096
```

### mDNS Access

If mDNS is enabled, use the friendly domain name:

```
mDNS:              opencode.local:4096
```

## Mobile and Remote Access

The web interface works on mobile devices:

1. Start the server with network access:
   ```bash theme={null}
   opencode web --hostname 0.0.0.0 --port 4096
   ```

2. On your mobile device, navigate to the network URL:
   ```
   http://192.168.1.100:4096
   ```

3. Add to home screen for app-like experience

## Configuration

Set default web server options in your global configuration (`~/.config/opencode/config.json`):

```json theme={null}
{
  "server": {
    "port": 4096,
    "hostname": "0.0.0.0",
    "mdns": true,
    "mdnsDomain": "myproject.local",
    "cors": []
  }
}
```

## Differences from Serve

The `web` command is similar to [`serve`](/cli/serve) but:

* Automatically opens a browser
* Shows formatted access URLs with visual styling
* Displays both local and network addresses when using `0.0.0.0`
* Filters out Docker bridge networks for cleaner output

Both commands expose the same HTTP API.

## Security Considerations

<Warning>
  Never expose an unauthenticated server to the internet. Use authentication and firewall rules.
</Warning>

* **Always** set `OPENCODE_SERVER_PASSWORD` for network access
* Use firewall rules to restrict access to trusted networks
* Consider using a reverse proxy with TLS for production
* Don't use Docker bridge IPs (filtered automatically)

## Troubleshooting

### Browser Doesn't Open

The command may fail to open the browser automatically in some environments (SSH sessions, headless servers, etc.). Simply copy the URL from the output and paste it into your browser.

### Can't Connect from Other Devices

1. Verify you used `--hostname 0.0.0.0`
2. Check firewall rules allow the port
3. Ensure devices are on the same network
4. Try the IP address instead of `localhost`

### mDNS Not Working

1. Ensure mDNS/Bonjour is installed on your system
2. Check that port 5353 (UDP) is not blocked
3. Verify both devices support mDNS
4. Try using the IP address as a fallback

## Related Commands

<CardGroup cols={2}>
  <Card title="serve" icon="server" href="/cli/serve">
    Start headless server without browser
  </Card>

  <Card title="attach" icon="link" href="/cli/attach">
    Attach TUI to running web server
  </Card>

  <Card title="Network Configuration" icon="network-wired" href="/network">
    Learn more about network setup
  </Card>

  <Card title="Server API" icon="code" href="/server">
    View full HTTP API documentation
  </Card>
</CardGroup>