AI Developer Tooling¶
Modal Sandboxes provides pre-configured integrations for popular AI developer tools and autonomous coding agent harnesses.
Integrated Tooling Matrix¶
| Tool | CLI Flag | Port / Ingress | Description |
|---|---|---|---|
| T3 Code | --t3 |
Port 3775 (Encrypted Tunnel) |
Visual coding agent harness with terminal, file editor, and mobile pairing QR. |
| Antigravity CLI | --agy |
Background Daemon | Google Gemini agent CLI and unattended remote control server. |
| OpenCode Server | --opencode |
Port 4096 (HTTPS Tunnel) |
Browser-based agent workspace with one-time password auth. |
| Pi Coding Agent | --pi |
System PATH (pi) |
Lightweight command-line coding assistant. |
| Herdr Multiplexer | --herdr |
/usr/local/bin/herdr |
Process orchestrator and terminal multiplexer. |
| Headless Chrome | --browser |
Local Headless | Pre-installed Google Chrome for Playwright, Puppeteer, and MCP servers. |
1. T3 Code Server (--t3)¶
Passing --t3 provisions the T3 Code server inside the sandbox:
- Starts t3code server on internal port 3775.
- Mounts the persistent Modal volume t3code-usage-v1 to /root/.t3/usage to retain session history across restarts.
- Generates an encrypted pairing URL and prints an ASCII QR code in your terminal on launch.
- Scan the QR code or click the pairing URL to connect your local IDE or browser directly to the sandbox.
2. Google Gemini Antigravity (--agy)¶
Passing --agy provisions Google's Antigravity developer agent environment:
- Reads ANTIGRAVITY_TOKENS from .env and provisions user profiles.
- Configures default writer models (gemini-2.5-pro / gemini-2.5-flash).
- Starts the Antigravity Remote Control background daemon for unattended agent execution (see ADR 0002).
3. OpenCode Go Server (--opencode)¶
Passing --opencode installs and starts the OpenCode server:
- Listens on port 4096.
- Connects through an HTTPS tunnel and prints a one-time login password on launch.
- Automatically provisions MCP server credentials via runtime secret injection.
4. Headless Chrome & Browser MCP (--browser)¶
Passing --browser pre-bakes a complete Google Chrome installation and required dependencies into the sandbox image layer (see ADR 0003):
- Compatible with Playwright, Puppeteer, and Chrome DevTools Protocol.
- Enables browser automation tools and MCP servers for visual verification and testing.