# Parselbox [Health: Active]

**Category:** 👨‍💻 Code Execution  
**Repository:** https://github.com/thesanjeetc/Parselbox  
**GitHub Stars:** 3  
**Views:** 1  
**Installs:** 0  
**Upvotes:** 0  
**Directory Page:** https://allmcps.com/mcp/parselbox

## Description
Secure Python sandbox — MCP servers, APIs, shells and host functions as native Python objects.

## Claude Desktop Quick Installation
Install path detected from listing signals. Uses `uvx` (confidence: high):

```json
"mcpServers": {
  "parselbox": {
    "command": "uvx",
    "args": ["parselbox"]
  }
}
```

## Documentation

## What Parselbox MCP server does

Parselbox MCP server provides an embeddable Python runtime for agent-driven code execution. It can expose configured MCP servers, REST and OpenAPI services, GraphQL endpoints, shell commands, and host-defined functions as Python objects. Agents can then combine those capabilities inside one execution instead of passing intermediate values through separate tool calls.

The runtime includes a disk-backed workspace, package installation, controlled networking, background tasks, and progressive discovery. Files created or changed during an execution can be returned to the caller. The API also supports rendering HTML through MCP Apps and serving a larger application with static files, uploads, live reload, and API routes.

## How it works

Parselbox MCP server uses Deno and Pyodide in one process. Deno supplies explicit filesystem and network permissions, while Pyodide provides the Python runtime. The project states that containers and microVMs are not required. Runtime controls include memory caps, execution timeouts, network allowlists, snapshot caching, and crash recovery.

A sandbox can connect to other MCP servers from a supplied configuration. Their tools become callable Python objects, with discovery functions such as `help()`, `search()`, `inspect()`, and `preview()` available to reveal capabilities as needed. Calls can be made directly or scheduled as background tasks with `.task()`, progress checks, log tailing, interactive `send()`, and later awaiting.

Python code can use installed packages and JavaScript interoperability. Imports may install packages automatically when enabled, and npm modules can be loaded through `require()`. WebAssembly modules can expose Python methods or callable WASI commands. The virtual `bash()` interface provides shell-style execution within the sandbox.

## Setup and configuration

Install Deno first, then install the Python package with `pip install parselbox`. The command-line MCP server can be added to an existing MCP configuration with `uvx parselbox`. Its `--mcp` option accepts a configuration file, and the HTTP transport can be selected with `--transport http` and a port such as `9000`.

The Python API accepts MCP configuration, host context objects, networking settings, runtime-package permissions, package lists, and an output directory. Filesystem access can use read-only or read-write host mounts. Input files are available under `/files/`, while generated outputs can be persisted to a configured directory.

## Tools and capabilities

The Parselbox MCP server supports:

- Executing Python code with state preserved across calls.
- Calling MCP, REST, OpenAPI, GraphQL, shell, and host-function integrations as Python objects.
- Discovering tools progressively with search, help, inspection, and previews.
- Running parallel or deferred work through background tasks.
- Reading, writing, and returning files from a disk-backed workspace.
- Using Python packages, npm modules, JavaScript, and WebAssembly components.
- Rendering inline HTML or serving a sandbox-hosted application.

## Limitations and notes

Parselbox MCP server still depends on Deno for its sandbox runtime, so Deno must be installed for the documented quick-start path. Runtime networking and filesystem access are permission-controlled rather than unrestricted. Host credentials remain outside the sandbox and are supplied through configured bridges or context objects.

The available tools depend on the MCP servers, APIs, shells, packages, mounts, and permissions supplied by the operator. Connecting the server to an MCP configuration should use an absolute path in the documented stdio example.

_Full upstream README: https://allmcps.com/mcp/parselbox/readme_