Zerobox

Zerobox is a local process sandbox for developers running AI agents, generated code, builds or tests with restricted access to their machine. It builds on OpenAI Codex's sandbox runtime and can contain a whole agent or individual tool calls.

• File access controls: Allow or deny reads and writes to specific paths, such as confining a build's output to one directory; writes are blocked by default.
• Network restrictions: Block outbound traffic by default, then allow or deny access by domain, including keeping tests from calling external services.
• Hidden credentials: Give a command placeholders instead of real API keys, with the real credentials substituted by a network proxy and optional restrictions on which hosts receive them.
• Filesystem rollback: Record filesystem changes and undo them after execution.
• Agent integration: Rust, TypeScript and Python SDKs let applications sandbox selected tool calls while the parent agent runs normally.

Zerobox runs on macOS and Linux as a single binary without Docker or a virtual machine. It's open source under Apache 2.0. By default, sandboxed commands inherit only essential environment variables rather than the parent's full environment.

Commands execute on your machine, but permitted API requests still go to the external services they call. Credential host restrictions are optional: without them, secrets can reach any domain permitted by the network policy.