OpenSandbox CLI

osb is the command-line interface for OpenSandbox. It is built for the common day-to-day flows:

• create and manage sandboxes
• build golden-image templates and create sandboxes from templates or snapshots
• run commands inside a sandbox
• read and modify sandbox files
• inspect runtime egress policy
• manage sandbox-local Credential Vault state
• collect low-level diagnostics
• install OpenSandbox-specific skills for coding agents

It uses the OpenSandbox Python SDK under the hood and is intended to be the shortest path from a terminal to a working sandbox workflow.

Install

Choose one:

pip install opensandbox-cli

uv tool install opensandbox-cli

pipx install opensandbox-cli

Confirm the install:

osb --help
osb --version

Before You Start

Make sure an OpenSandbox server is reachable. If you are running locally, start the server first and then point the CLI at it.

opensandbox-server

Quick Start

1. Initialize config

osb config init
osb config set connection.domain localhost:8080
osb config set connection.protocol http
osb config set connection.api_key <your-api-key>
osb config show -o json

If you want a non-default config file, choose it at the root command level for the whole invocation:

osb --config /tmp/dev.toml config init
osb --config /tmp/dev.toml config set connection.domain localhost:8080
osb --config /tmp/dev.toml config show -o json

2. Create a sandbox

osb sandbox create --image python:3.12 --timeout 30m -o json

If you set defaults first, later create commands can be shorter:

osb config set defaults.image python:3.12
osb config set defaults.timeout 30m
osb sandbox create -o json

3. Verify it is usable

osb sandbox get <sandbox-id> -o json
osb sandbox health <sandbox-id> -o json

4. Run a command inside the sandbox

Use -- before the sandbox command payload.

osb command run <sandbox-id> -o raw -- python -c "print(1 + 1)"

5. Read or write a file

osb file write <sandbox-id> /workspace/hello.txt -c "hello" -o json
osb file cat <sandbox-id> /workspace/hello.txt -o raw

6. Clean up

osb sandbox kill <sandbox-id> -o json

Common Tasks

Create sandboxes

Basic:

osb sandbox create --image python:3.12

Private image:

osb sandbox create \
  --image my-registry.example.com/team/app:latest \
  --image-auth-username alice \
  --image-auth-password <token>

Manual cleanup mode:

osb sandbox create --image python:3.12 --timeout none

Explicit entrypoint argv:

osb sandbox create \
  --image python:3.12 \
  --entrypoint python \
  --entrypoint -m \
  --entrypoint http.server

Create with network policy and volumes:

osb sandbox create \
  --image python:3.12 \
  --network-policy-file network-policy.json \
  --volumes-file volumes.json

Create with Credential Vault proxy enabled:

osb sandbox create --image python:3.12 --network-policy-file network-policy.json --credential-proxy -o json

Create from a template (golden image):

osb sandbox create --template <template-id> --timeout 30m -o json

Template mode fixes the workload shape on the server: --image, --env, --resource, --entrypoint, --volumes-file, and --credential-proxy cannot be combined with --template. Only --timeout (required), --metadata, --extension, and --network-policy-file may accompany it. Only templates in the Succeeded phase can be used. See Manage templates.

Create from a snapshot:

osb sandbox create --snapshot-id <snapshot-id> --timeout 30m -o json

--image, --template, and --snapshot-id are mutually exclusive.

Create from a request file (-f, like kubectl apply -f):

osb sandbox create -f sandbox-request.json -o json

sandbox-request.json uses the public CreateSandboxRequest JSON format (camelCase keys):

{
  "image": "python:3.12",
  "timeout": 1800,
  "resourceLimits": { "cpu": "1", "memory": "2Gi" },
  "entrypoint": ["python", "-m", "http.server"],
  "networkPolicy": {
    "defaultAction": "deny",
    "egress": [{ "action": "allow", "target": "pypi.org" }]
  }
}

• Exactly one of image (string or { "uri": ..., "auth": { "username": ..., "password": ... } }), templateId, or snapshotId is required; timeout is integer seconds, or null for manual cleanup.
• Supported fields: image, templateId, snapshotId, platform, timeout, resourceLimits, resourceRequests, env, metadata, extensions, entrypoint, networkPolicy, credentialProxy, secureAccess, volumes, lifecycle.
• -f cannot be combined with request-building flags; --skip-health-check, --ready-timeout, and -o still apply. In template mode the file may only set timeout, metadata, extensions, and networkPolicy alongside templateId (a finite timeout is required).

Manage templates

Templates are golden-image builds; the build runs asynchronously, so poll template get until the status phase is Succeeded. Template management requires a Kubernetes-backed runtime.

osb template create --image python:3.12 --publish s3://bucket/publish -o json
osb template get <template-id> -o json
osb template list -o json
osb template delete <template-id> -o json

template create also accepts --resource cpu=1 memory=512Mi disk=2Gi, --entrypoint (repeat per argv item), --env KEY=VALUE, --metadata KEY=VALUE, --format native|overlaybd, --readiness-probe, and --warmup-seconds. Or pass a request file in the public CreateTemplateRequest JSON format:

osb template create -f template-request.json -o json

{
  "image": "python:3.12",
  "publish": "s3://bucket/publish",
  "resourceLimits": { "cpu": "1", "memory": "512Mi" },
  "readiness": { "probe": "tcp://127.0.0.1:44772", "warmupSeconds": 60 }
}

Manage snapshots

Snapshots capture a sandbox's state and can back new sandboxes.

osb snapshot create <sandbox-id> --name golden -o json
osb snapshot get <snapshot-id> -o json
osb snapshot list --sandbox-id <sandbox-id> -o json
osb snapshot delete <snapshot-id> -o json

List and inspect sandboxes

osb sandbox list
osb sandbox list -o json
osb sandbox list --state running --state paused
osb sandbox get <sandbox-id> -o json
osb sandbox metrics <sandbox-id>
osb sandbox metrics <sandbox-id> --watch -o raw

Pause a sandbox

Pause is asynchronous. Pause request accepted confirms that the server accepted the request, not that the sandbox has reached the Paused state. Poll the sandbox until the transition finishes:

osb sandbox pause <sandbox-id>
osb sandbox get <sandbox-id> -o json

Expose a service

osb sandbox endpoint <sandbox-id> --port 8080 -o json

Run commands

Foreground streaming:

osb command run <sandbox-id> -o raw -- sh -lc 'echo ready'

Tracked background execution:

osb command run <sandbox-id> --background -o json -- sh -c "sleep 10; echo done"
osb command status <sandbox-id> <execution-id> -o json
osb command logs <sandbox-id> <execution-id> -o json

Background start errors or a stream ending before startup confirmation make the CLI exit non-zero without success metadata. After a successful start, use command status and command logs to check the process's eventual result.

By default the payload after -- is joined into one shell command string, so pipelines, redirection, and $VAR expansion work as in a terminal. Add --argv to pass the arguments to the executable as a literal argv list (no shell) when values such as $HOME, quotes, embedded spaces, or empty strings must reach the process unchanged. --argv needs a sandbox image whose execd accepts argv requests:

osb command run <sandbox-id> -o raw --argv -- python3 -c "import sys; print(sys.argv[1:])" "a b" '$HOME' "x'y" ""

Persistent shell session:

osb command session create <sandbox-id> --workdir /workspace -o json
osb command session run <sandbox-id> <session-id> -o raw -- pwd
osb command session run <sandbox-id> <session-id> -o raw -- export FOO=bar
osb command session run <sandbox-id> <session-id> -o raw -- sh -c 'echo $FOO'
osb command session delete <sandbox-id> <session-id> -o json

Open an interactive terminal

osb terminal attaches your current terminal to a real PTY inside the sandbox (colors, stty, and resize all behave like a local shell). Exit the remote shell (or press Ctrl-D) to leave; the remote exit code becomes the command's exit code.

osb terminal <sandbox-id>
osb terminal <sandbox-id> -w /workspace

Requires an interactive TTY, and is supported on Unix, macOS, and Linux. If the connection drops while the shell is still running, the session is kept server-side and its id is printed so it can be inspected or removed via the execd API; a clean exit tears the session down.

Work with files

osb file upload <sandbox-id> ./local.txt /workspace/local.txt -o json
osb file download <sandbox-id> /workspace/result.json ./result.json -o json
osb file search <sandbox-id> /workspace --pattern "*.py" -o json
osb file info <sandbox-id> /workspace/main.py -o json
osb file replace <sandbox-id> /workspace/app.py --old old --new new -o json
osb file chmod <sandbox-id> /workspace/script.sh --mode 755 -o json

Downloads replace regular files only on success; a failed or interrupted download preserves any existing regular file. Existing devices and named pipes receive data directly. Stdout aliases (such as /dev/stdout) stream only the file bytes, without a success message. See the CLI guide.

Manage runtime egress policy

Inspect current policy:

osb egress get <sandbox-id> -o json

Patch specific rules:

osb egress patch <sandbox-id> --rule allow=pypi.org --rule deny=internal.example.com -o json

If you are debugging connectivity, verify behavior with an actual command:

osb command run <sandbox-id> -o raw -- curl -I https://pypi.org

Manage Credential Vault

Credential Vault operations call the sandbox egress sidecar through the Python SDK. Create the sandbox with --credential-proxy and an explicit network policy before writing vault state.

osb credential-vault create <sandbox-id> --file vault.yaml -o json
osb credential-vault get <sandbox-id> -o json
osb credential-vault patch <sandbox-id> --file mutation.yaml -o json
osb credential-vault credential list <sandbox-id> -o json
osb credential-vault binding list <sandbox-id> -o json
osb credential-vault delete <sandbox-id> -o json

Use --file - to read a JSON/YAML payload from stdin. Do not pass plaintext credential values as command-line flags; keep them in the payload stream or file.

Collect diagnostics

Use context to identify the runtime backend, then collect log and event descriptors.

osb diagnostics context <sandbox-id> -o json
osb diagnostics events <sandbox-id> --scope runtime -o raw
osb diagnostics events <sandbox-id> --scope all -o raw
osb diagnostics logs <sandbox-id> --scope container -o raw
osb diagnostics logs <sandbox-id> --scope all -o json
osb diagnostics events <sandbox-id> --scope runtime -o json
osb diagnostics logs <sandbox-id> --scope container -o yaml

context returns backend routing information without connecting to execd and supports table, JSON, and YAML output. --scope is required for logs/events. The built-in server supports container and all for logs, and runtime and all for events. It returns DIAGNOSTICS_SCOPE_UNSUPPORTED for unavailable scopes, including lifecycle events. Best-effort scopes may include a warnings field when the backend can only provide a subset. Raw output prints inline diagnostic text, or the content URL when diagnostics are delivered as a temporary URL. Structured CLI output follows the SDK/Python field style, for example content_url, content_length, and expires_at. Older server builds may still return DIAGNOSTICS_NOT_IMPLEMENTED for scoped diagnostics.

Legacy DevOps diagnostics remain experimental. Prefer osb diagnostics logs/events for stable API-backed log and event collection.

osb devops inspect <sandbox-id> -o raw
osb devops summary <sandbox-id> -o raw

Output Formats

Output selection is command-scoped, not global.

• table: human-readable tables and panels
• json: machine-readable JSON
• yaml: machine-readable YAML
• raw: unformatted text or streaming output

Examples:

osb sandbox list -o json
osb sandbox list -o yaml
osb file cat <sandbox-id> /workspace/hello.txt -o raw

Not every command supports every format. Use --help on the specific command when in doubt.

Command Groups

The main command groups are:

• osb sandbox: lifecycle management
• osb template: golden-image template builds
• osb snapshot: snapshot management
• osb command: command execution and persistent sessions
• osb terminal: interactive PTY terminal into a sandbox
• osb file: file and directory operations
• osb egress: runtime egress policy
• osb diagnostics: stable diagnostics logs and events
• osb devops: experimental legacy diagnostics
• osb config: local CLI configuration
• osb skills: bundled skills for AI tools

Explore them directly:

osb sandbox --help
osb template --help
osb snapshot --help
osb command --help
osb file --help
osb skills --help

Agent Skills

The CLI ships with built-in OpenSandbox skills for coding agents and agent-oriented tools.

Bundled skills:

• sandbox-lifecycle
• command-execution
• file-operations
• network-egress
• sandbox-troubleshooting

Supported targets:

Target	Install location
claude	./.claude/skills/<name>/SKILL.md or ~/.claude/skills/<name>/SKILL.md
cursor	./.cursor/rules/ or ~/.cursor/rules/
codex	./.codex/skills/<name>/SKILL.md or ~/.codex/skills/<name>/SKILL.md
copilot	./.github/copilot-instructions.md or ~/.copilot/copilot-instructions.md
windsurf	./.windsurfrules or ~/.windsurfrules
cline	./.clinerules or ~/.cline/rules/opensandbox-<name>.md
opencode	./.agents/skills/<name>/SKILL.md or ~/.agents/skills/<name>/SKILL.md

Common flows:

osb skills list
osb skills show sandbox-lifecycle
osb skills install sandbox-lifecycle --target codex --scope project
osb skills install --all-builtins --target codex --scope global
osb skills uninstall sandbox-troubleshooting --target claude --scope global

For scripts or agents, use structured output:

osb skills install sandbox-lifecycle --target codex --scope project -o json

Configuration Model

The CLI resolves configuration in this order:

1. root CLI flags such as --api-key, --domain, --protocol, --request-timeout, --config
2. environment variables such as OPEN_SANDBOX_API_KEY and OPEN_SANDBOX_DOMAIN
3. config file, defaulting to ~/.opensandbox/config.toml
4. SDK defaults

Config commands:

osb config init
osb config show
osb config set connection.domain localhost:8080
osb config set connection.protocol http
osb config set defaults.image python:3.12
osb config set defaults.timeout 30m

Example config file:

[connection]
api_key = "your-api-key"
domain = "localhost:8080"
protocol = "http"
request_timeout = 30
use_server_proxy = false

[output]
color = true

[defaults]
image = "python:3.12"
timeout = "30m"

Development

For local development in this monorepo:

cd cli
uv sync
uv run osb --help
uv run pytest

This repository uses a local uv source override for the OpenSandbox Python SDK, so running from cli/ will resolve against the checked-out SDK in the monorepo.