Code Sandbox X402 MCP Server

@Br0ski777

Basic information

About Code Sandbox X402 MCP Server

Execute Python, JavaScript, or SQL in a sandbox. Get stdout, execution time, errors. 10s timeout. -- x402 micropayment API + MCP server for AI agents

#x402 #mcp #api #sandbox #code-execution #python #javascript #sql #ai-agent

Code Sandbox X402 MCP Server config

Add this server to your MCP-compatible client using the configuration below.

{
  "mcpServers": {
    "code-sandbox": {
      "url": "https://code-sandbox-production-9b5e.up.railway.app/mcp",
      "transport": "sse"
    }
  }
}

Code Sandbox X402 MCP Server tools

POST

Overview

What is Code Sandbox X402?

Code Sandbox X402 executes Python, JavaScript, or SQL code in a sandboxed environment and returns stdout, execution time, errors, and exit codes. It uses a pay-per-call model via the x402 protocol (USDC on Base L2), requiring no API key, signup, or rate-limit wall. It is part of the klymax402 marketplace of micropayment APIs for AI agents.

How to use Code Sandbox X402?

Add the server to an MCP client configuration (Claude Desktop, Cursor, ElizaOS) using the URL https://code-sandbox.api.klymax402.com/mcp. Alternatively, call the HTTP endpoint directly with a POST request; any x402-aware client automatically handles the 402 payment challenge and retry cycle.

Key features of Code Sandbox X402

Execute Python, JavaScript, or SQL in a sandbox
Pay-per-call using USDC on Base L2 via x402
No API key, signup, or rate-limit walls
10-second maximum execution timeout (configurable to 5,000 ms default)
Returns stdout, execution time, exit code, and error messages
Output limited to 10 KB

Use cases of Code Sandbox X402

Running calculations or data transformations on demand
Validating code snippets before production use
Querying in-memory SQLite databases for computed results
Enabling AI agents to execute code without exposing a full runtime

Frequently asked questions

What programming languages are supported?

Python (subprocess), JavaScript (eval), and SQL (in-memory SQLite).

What is the execution timeout?

The default timeout is 5,000 ms, with a maximum of 10,000 ms.

How does payment work?

Payment uses the x402 protocol – a HTTP-native pay-per-call system – on Base L2 (network `eip155:8453`) with USDC. No signup or API key is required; the first request returns a 402 challenge, and an x402‑aware client automatically signs and retries.

Is there an output size limit?

Yes, stdout is capped at 10 KB.

Where is the server hosted?

It is part of the klymax402 marketplace. The full API reference and catalog are available at klymax402.com.

Comments

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