basic-mcp

basic-mcp

MCP server providing deterministic tools for operations that LLMs commonly struggle with: time, math, counting, randomness, and validation.

Installation

bun install

Usage

With Claude Code

Add to ~/.claude.json:

{
  "mcpServers": {
    "basic-tools": {
      "command": "bun",
      "args": ["run", "/path/to/basic-mcp/index.ts"]
    }
  }
}

Standalone

bun run index.ts

Tools

Time

Tool	Description
now	Get current date/time with timezone support
date_diff	Calculate difference between two dates
date_add	Add/subtract time from a date
unix_timestamp	Convert between Unix timestamps and dates

Math

Tool	Description
calculate	Evaluate math expressions (supports "15% of 200", sqrt, trig, etc.)
convert_units	Convert between units (km to miles, celsius to fahrenheit, etc.)
statistics	Calculate mean, median, mode, std dev, min, max, sum

Strings

Tool	Description
count	Count characters, words, lines, bytes, sentences, paragraphs
hash	Generate MD5, SHA1, SHA256, SHA512 hashes
uuid	Generate UUID v4
base64	Encode/decode base64
regex_test	Test strings against regex patterns

Random

Tool	Description
random_int	Cryptographically secure random integer
random_float	Cryptographically secure random float
random_choice	Select random item(s) from a list
shuffle	Randomly shuffle an array (Fisher-Yates)

Validation

Tool	Description
validate	Validate email, URL, IPv4, IPv6, UUID, JSON, credit card (Luhn)
json_parse	Parse JSON with optional path extraction
url_parse	Parse URL into components
dns_lookup	DNS lookup (A, AAAA, MX, TXT, NS, CNAME records)

License

MIT