Default Policy Reference

Breakdown of the built-in default policy applied when you create an OpenShell sandbox without a custom policy.

Default policy reference

The default policy is applied when you create an OpenShell sandbox without --policy. It is baked into the community base image (ghcr.io/nvidia/openshell-community/sandboxes/base) and defined in the community repo’s dev-sandbox-policy.yaml.

Agent compatibility

The default policy is authored for Claude Code. Other agents require additional policy configuration.

Agent	Coverage	Action required
Claude Code	Full	None. Works out of the box.
OpenCode	Partial	Add opencode.ai endpoint and OpenCode binary paths.
Codex	None	Provide a complete custom policy with OpenAI endpoints and Codex binary paths.

If you run a non-Claude agent without a custom policy, the agent’s API calls are denied by the network proxy. You must provide a policy that declares the agent’s endpoints and binaries.

Default filesystem access

The default policy grants the following filesystem access inside the sandbox:

Path	Access	Purpose
/usr	Read-only	System binaries and libraries
/lib	Read-only	Shared libraries
/lib64	Read-only	64-bit shared libraries
/proc	Read-only	Process information filesystem
/dev/urandom	Read-only	Entropy source
/etc	Read-only	System configuration
/sandbox	Read-write	Agent working directory
/tmp	Read-write	Temporary files
/dev/null	Read-write	Null device

The include_workdir: true flag is set by default, so the agent’s current working directory is always included in read-write access.

Default network access

The default policy’s network rules are defined in dev-sandbox-policy.yaml in the community repository. The policy covers the endpoints and binaries required by Claude Code, including the Anthropic API and common development tooling.

The full dev-sandbox-policy.yaml source is maintained in the openshell-community repository. Refer to that repository for the current list of permitted hosts, ports, and binaries.

Viewing the active policy

To inspect the policy currently applied to a sandbox:

openshell policy get <sandbox-name>

This returns the full policy YAML, including both the default blocks and any custom extensions you have applied.

Extending the default policy

Use openshell policy set to apply a policy file to a running sandbox. Because network_policies is a dynamic section, changes take effect immediately without restarting the sandbox.

openshell policy set <sandbox-name> --policy ./my-policy.yaml

Your policy file is merged with the default policy blocks. You do not need to redeclare the default filesystem or process settings unless you want to override them.

Start from the community dev-sandbox-policy.yaml and add your agent’s endpoints and binary paths. This preserves the default Claude Code coverage while adding support for your agent.

Policy schema

Complete field reference for all policy YAML fields.

Support matrix

Supported platforms, prerequisites, and kernel requirements.