sandbox-as-a-service-mcp
An MCP server that gives an agent a real Linux virtual machine it
can break.
Eleven tools: create a sandbox, run shell commands in it, write and read files, list what a run
produced, expose a port on a public preview URL, extend the lifetime, destroy it, and check what it
all cost.
Each sandbox is a dedicated VM with its own kernel — not a container sharing a host with other
people's code. It is never reused between accounts and is destroyed when it expires, whether or not
anything remembered to ask.
Use it
Maintained by the operator of Sandbox as a Service.
Hosted MCP (no local package)
For a client that supports Streamable HTTP, connect to:
https://sandbox-as-a-service.com/v1/mcp
Send your own API key on each request as Authorization: Bearer <your-api-key>
or x-api-key: <your-api-key>. Get it at
Dashboard → API keys.
Never put an API key in the URL or share one through a registry.
The hosted server exposes 12 tools: the eleven account/execution tools below
plus get_service_info. Anonymous initialize, tools/list, and
get_service_info work for free hosted discovery; account and execution calls
still require your key. The local stdio server (including the current downloadable
mcp.tgz v1.1.0) exposes the eleven account/execution tools. Use the hosted endpoint
for keyless service information. A GET-only check is not a connection test: this
endpoint uses MCP POST requests and SSE responses.
On Smithery,
set apiKey to your own raw key; it maps to the x-api-key header.
Connection documentation.
Local stdio (current hosted package)
AAS_API_KEY=aas_sk_... npx -y https://sandbox-as-a-service.com/mcp.tgz
Get a key at sandbox-as-a-service.com — new accounts start with
free credit and no card.
Claude Desktop / Claude Code
{
"mcpServers": {
"sandbox": {
"command": "npx",
"args": ["-y", "https://sandbox-as-a-service.com/mcp.tgz"],
"env": { "AAS_API_KEY": "aas_sk_..." }
}
}
}
| Tool | What it does |
|---|
create_sandbox | Creates a VM and returns its id once it is ready. |
run_command | Runs a shell command as an unprivileged user. Returns stdout, stderr, exit code. |
write_file | Writes a file. Content travels out of band, so quotes and binary survive. |
read_file | Reads a file back — how an agent gets at what its code produced. |
list_files | Lists a directory tree, so an agent can find what a run produced. |
expose_port | Gives a server inside the sandbox a public https URL to share. |
get_sandbox | Status, size and expiry. |
list_sandboxes | Everything on the account, newest first — useful for finding strays. |
extend_sandbox | Pushes the expiry out when a job outgrows its timeout. |
destroy_sandbox | Destroys it and stops billing. |
get_usage | Remaining credit and recent usage. |
Notes for agents
- Code runs as an unprivileged user. There is no
sudo, so apt-get will not work; use
pip install --user --break-system-packages or npm install, both of which do.
run_command waits for the command to finish. Start a server with & or it will hold the call
open until the timeout.
- A sandbox is destroyed when its timeout expires whether or not
destroy_sandbox is called, so a
forgotten sandbox costs minutes, not money forever. Calling it anyway returns the minutes you were
not going to use.
Environment
| Variable | |
|---|
AAS_API_KEY | Required. Your API key. |
AAS_BASE_URL | Optional. Defaults to https://sandbox-as-a-service.com. Use the origin only, without /v1; the client adds that API prefix. |
MIT licensed. The service it talks to is at
sandbox-as-a-service.com;
docs.