About nerd-utility-api
nerd-utility-api is a JSON utility microservice for developers and agents, with endpoints for formatting, validation, conversion, and lookup tasks. Its OpenAPI-based package also provides MCP tools for accessing the API.
Key features
- 01JSON input and output
- 02Formatting and conversion endpoints
- 03Validation, decoding, and hashing
- 04DNS, weather, and scraping endpoints
- 05OpenAPI catalog and MCP package
Use cases
- 01Convert CSV and JSON data
- 02Validate JWTs and regular expressions
- 03Look up DNS and WHOIS information
- 04Call utility endpoints from MCP clients
MCP support
The included npm package provides 23+ tools generated from the OpenAPI specification. Set NERD_API_URL to direct the tools to an instance.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://feminine-neatness-coliseum.ngrok-free.dev/mcpclaude mcp add --transport http dohyeopsong-nerd-utility-api https://feminine-neatness-coliseum.ngrok-free.dev/mcp{"mcpServers":{"dohyeopsong-nerd-utility-api":{"type":"http","url":"https://feminine-neatness-coliseum.ngrok-free.dev/mcp"}}}Open in Cursor{"servers":{"dohyeopsong-nerd-utility-api":{"type":"http","url":"https://feminine-neatness-coliseum.ngrok-free.dev/mcp"}}}Open in VS Code{"mcpServers":{"dohyeopsong-nerd-utility-api":{"type":"http","url":"https://feminine-neatness-coliseum.ngrok-free.dev/mcp"}}}{"mcpServers":{"dohyeopsong-nerd-utility-api":{"serverUrl":"https://feminine-neatness-coliseum.ngrok-free.dev/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project READMENerd Utility API
A fast, free utility micro-service with 45+ endpoints — data formatting, validators, decoders, converters, and more. No auth, no rate limits, JSON in / JSON out.
Base URL: set via NERD_API_URL env var (default http://localhost:8080).
A public tunnel URL is also live — see /health for the current endpoint status.
Quick start
curl "http://localhost:8080/base64?text=aGVsbG8="
curl "http://localhost:8080/semver?a=1.2.3&b=1.2.10"
curl "http://localhost:8080/cron?expr=0%209%20*%20*%201-5"
Endpoints (highlights)
format, csv2json, json2csv, base64, hash, uuid, timestamp, validate, regex, weather, whois, dns, headers, price, ipinfo, scrape, qrcode, isbn, iban, barcode (EAN/UPC), vin, password, cron, semver, jwt, units, diff, markdown, shorten, rss, og, cert, ua-parse, alerts, stats, docs, openapi.json, llms.txt
Full machine-readable catalog: /openapi.json (OpenAPI 3.0) and /llms.txt.
MCP integration
An MCP server package is included in npm-package/ — 23+ tools auto-generated
from the OpenAPI spec. Set NERD_API_URL to point the tools at your instance.
License
MIT
Comments
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