Casper Tools — MCP server (12 agent utilities)

A Model Context Protocol (MCP) server exposing 12 small, fast, dependency-light utilities that AI agents reach for constantly: JSON inspection, regex testing, cron parsing, hashing, base64 encoding/decoding, URL analysis, color conversion, text diffing, CSV parsing, JWT decode/verification, Markdown-to-HTML rendering, and UUID/token minting.

Transport: Streamable HTTP. Auth: none (open public endpoint). No API keys. Free to use.

Live endpoint

https://determines-product-administration-farmer.trycloudflare.com

Related MCP server: mcp-server-devutils

Quick Example

Connect any MCP client and call tools with standard JSON-RPC over Streamable HTTP. No auth, no keys, no setup.

Initialize the session:

{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}

Call json_inspect on a sample payload:

{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"json_inspect","arguments":{"data":{"user":"alice","role":"admin"}}}}

Response includes type, summary, keyCount, depth, and hasArrays.

Call hash_compute on a string:

{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"hash_compute","arguments":{"input":"hello world","algorithm":"sha-256"}}}

Response returns the hex-encoded digest plus algorithm + input length.

Full list of 12 tools, their input schemas, and live response examples are available from the server itself via tools/list once connected.

Tools

Install

Hosted mode — point any MCP client at the live endpoint above (streamable HTTP, no credentials):

{
  "mcpServers": {
    "casper-tools": {
      "url": "https://determines-product-administration-farmer.trycloudflare.com"
    }
  }
}

Local mode (Claude Code / Cursor / any MCP client):

{
  "mcpServers": {
    "casper-tools": {
      "command": "npx",
      "args": ["-y", "casper-tools"]
    }
  }
}

Operation

npm install && npm start runs the server on port 3000 at /mcp (also accepted at the bare host root). Tools are registered from tools.js and each call is appended to logs/calls.jsonl for analytics.

Repo

Source lives in this repository. Published to the official MCP Registry as io.github.magiautonomous/casper-tools. MIT licensed.