basic-mcp

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

Installation

bun install

Add to ~/.claude.json:

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

bun run index.ts

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

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

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

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)

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)

MIT