# yepcode/mcp-server-js [Health: Active]

**Category:** 👨‍💻 Code Execution  
**Repository:** https://github.com/yepcode/mcp-server-js  
**GitHub Stars:** 47  
**npm Downloads (last month):** 86  
**Views:** 3  
**Installs:** 0  
**Upvotes:** 0  
**Directory Page:** https://allmcps.com/mcp/yepcode-mcp-server-js

## Description
Execute any LLM-generated code in a secure and scalable sandbox environment and create your own MCP tools using JavaScript or Python, with full support for NPM and PyPI packages

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

```json
"mcpServers": {
  "mcp-server-js": {
    "command": "npx",
    "args": ["-y","@yepcode/mcp-server"],
    "env": {
      "YEPCODE_API_TOKEN": ""
    }
  }
}
```

**Requires environment variables:** `YEPCODE_API_TOKEN` — the values above are empty placeholders; fill in real credentials before running (see the repository for what each one is for).

## Documentation

## What yepcode/mcp-server-js MCP server does

The yepcode/mcp-server-js MCP server connects an MCP-compatible AI platform to YepCode’s infrastructure. Its primary code-execution tool, `run_code`, sends JavaScript or Python to YepCode’s isolated environment and returns the execution result, console logs, or an error. Execution options can include the language, a comment describing the context, and runtime settings.

YepCode processes can also become MCP tools. Processes selected by tag are exposed individually, allowing a workspace to publish workflows with their own inputs and JSON Schema definitions. These tools can use OAuth, API tokens, or existing YepCode credentials according to the workspace’s security model. A single server can expose processes implemented in Node.js, Python, or both.

The server also supports YepCode management capabilities. Depending on configuration, these include process, schedule, variable, storage, execution, and module operations, along with version-management tools in the full API set.

## How it works

The yepcode/mcp-server-js MCP server runs locally or in infrastructure you control and communicates with the MCP client over its configured transport. YepCode provides a hosted endpoint at `https://cloud.yepcode.io/mcp` for accounts that use the hosted service instead.

Tool exposure is controlled with `YEPCODE_MCP_TOOLS`. Built-in selections include `run_code`, `yc_api`, and `yc_api_full`; individual API tool names can also be selected. Adding a process tag exposes every matching process as an MCP tool. If this variable is omitted, built-in tools are enabled by default, while tagged process tools are not exposed.

`YEPCODE_MCP_OPTIONS` accepts comma-separated options. `runCodeCleanup` controls whether source created for `run_code` is removed after execution, and `skipCodingRules` omits the JavaScript and Python guidance included in the `run_code` schema.

## Setup and configuration

Create a YepCode API token under the account’s API credentials settings, then provide it as `YEPCODE_API_TOKEN`. With Node.js 18 or later installed, an MCP client can launch the package through NPX using `npx -y @yepcode/mcp-server`. Docker users can build the repository image and pass the token into the container as an environment variable.

Cursor and Claude Desktop are named as supported integration targets in the README. For stdio troubleshooting, the project recommends the MCP Inspector, which can be started with `npm run inspector` and accessed in a browser.

## Tools and capabilities

The yepcode/mcp-server-js MCP server documents these tool groups and operations:

- `run_code`: execute code and receive a return value, logs, or an error.
- `set_env_var` and `remove_env_var`: manage workspace environment variables; values can be marked sensitive when set.
- `list_files`: list files in YepCode storage. The storage system also supports uploading, downloading, and deleting files for use by executions.
- API management tools for processes, schedules, variables, storage, executions, and modules.
- Process tools selected by tags, named from the process slug or, for long names, a generated name using the process ID.

The project description also identifies NPM and PyPI package support for generated JavaScript and Python code. Exact available packages and runtime limits are determined by the YepCode environment rather than by the MCP configuration shown here.

## Limitations and notes

An API token is required for the documented local NPX or Docker setup. The server delegates execution and workspace operations to YepCode, so access, credentials, process configuration, and security behavior depend on the connected YepCode account.

Leaving `YEPCODE_MCP_TOOLS` unset exposes built-in tools but does not publish tagged processes. Selecting `yc_api_full` extends the basic API set with version-related process and module tools. Source cleanup is enabled by default for `run_code`; use the documented option when retaining source for audit purposes is required.

_Full upstream README: https://allmcps.com/mcp/yepcode-mcp-server-js/readme_