Omnibox
Omnibox is Omnigent's secure OS-level sandbox. It wraps any agent (Claude Code, Codex, or a custom agent) so you can run it unattended, in YOLO mode, without handing it your real credentials, file system, or network.
The kernel enforces the rules, not the agent or its prompt: bubblewrap and
seccomp on Linux, Seatbelt (sandbox-exec) on macOS. Every process
the agent spawns inherits the boundary, so a prompt-injected or misbehaving agent can't
opt out.
Omnibox combines three protections:
- Filesystem isolation
- Network isolation
- Credential injection
Filesystem isolation
The agent sees only the paths you grant; everything else doesn't exist from inside the
sandbox. Even cwd is read-only until you opt directories back in, so a runaway
agent can't read your SSH keys or write outside the workspace.
Broad read grants stay safe: granting ~ doesn't expose ~/.ssh or
~/.aws/credentials, because dotfiles are masked unless you allow them.
See the filesystem settings for read and write grants, denied paths, and path expansion behavior.
Network isolation
When you configure egress_rules, HTTP(S) traffic goes through a default-deny proxy
with an explicit allow-list of methods, hosts, and paths. Data can't leave except to
hosts you chose, which shuts down exfiltration even if the agent is prompt-injected.
Private IPs and cloud metadata endpoints are blocked by default, so the agent can't reach your internal services.
See the network settings for allowed hosts, methods, paths, and localhost access.
Credential injection
The agent holds a fake placeholder token instead of the real secret. When a request matching your allow-list leaves the sandbox, the proxy swaps in the real credential. The agent can use a credential but never read it.
Only the placeholder appears in logs, transcripts, and model context. A leaked token is worthless, since it only works through the proxy, against allowed hosts.
See credential injection for placeholder mappings, secret sources, and supported authentication flows.
Related
- OS sandbox configuration: the full reference, covering filesystem grants, egress rules, environment passthrough, and the
bubblewrap/Seatbelt backends. - Cloud sandbox host: controls where the runner executes. Omnibox controls what it can access. They compose.
- Contextual policies: govern behavior at the tool-call level. Omnibox is the hard boundary underneath.