MCP Server

New

Call every Vothlab tool directly from Claude, Cursor, or any MCP-compatible LLM client — no copy-pasting into a browser tab.

@vothlab/mcp-server Source on GitHub

What is MCP?

The Model Context Protocol is an open standard that lets LLM clients — Claude Desktop, Claude Code, Cursor, and others — call external tools during a conversation. The Vothlab MCP server exposes 16 of our developer tools (encoding, hashing, generation, format conversion, regex, diff) as MCP tools, so an LLM can call hash_generate oruuid_generate mid-conversation instead of you switching tabs. All tools are free and deterministic — no LLM calls happen inside the server itself, no data is retained.

Install & Connect

Point any client that supports remote (Streamable HTTP) MCP servers straight at the hosted endpoint — nothing to install.

claude-code

claude mcp add --transport http vothlab https://mcp.vothlab.com

Or add it manually to your client's MCP config (Claude Desktop, Cursor, etc.):

mcp.json

{
  "mcpServers": {
    "vothlab": {
      "url": "https://mcp.vothlab.com"
    }
  }
}

Quick Example

Once connected, just ask your LLM client naturally — e.g. “generate a UUID and hash it with SHA-256”. Under the hood, the client sends a JSON-RPC tools/call request like this:

request

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "hash_generate",
    "arguments": {
      "input": "vothlab",
      "algorithm": "sha256"
    }
  }
}

response

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "content": [
      {
        "type": "text",
        "text": "0ae85bf797ef2a640186a5c056aac0e57143ff368414f71b297441e4f2da6f3c"
      }
    ],
    "isError": false
  }
}

Full API Reference — 16 Tools

Encode & Decode

base64_encode

Encode UTF-8 text to Base64.

Parameters

Param	Type	Default	Description
input*	string	—	Text to encode

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "base64_encode",
    "arguments": {
      "input": "hello world"
    }
  }
}

Response

result

aGVsbG8gd29ybGQ=

base64_decode

Decode a Base64 string to UTF-8 text.

Parameters

Param	Type	Default	Description
input*	string	—	Base64 string to decode

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "base64_decode",
    "arguments": {
      "input": "aGVsbG8gd29ybGQ="
    }
  }
}

Response

result

hello world

url_encode

URL-encode a string (percent-encoding).

Parameters

Param	Type	Default	Description
input*	string	—	Text to encode

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "url_encode",
    "arguments": {
      "input": "a b/c"
    }
  }
}

Response

result

a%20b%2Fc

url_decode

URL-decode a percent-encoded string.

Parameters

Param	Type	Default	Description
input*	string	—	Percent-encoded text to decode

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "url_decode",
    "arguments": {
      "input": "a%20b%2Fc"
    }
  }
}

Response

result

a b/c

jwt_decode

Decode a JWT's header, payload, and expiry. Does NOT verify the signature.

Parameters

Param	Type	Default	Description
token*	string	—	The JWT to decode

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "jwt_decode",
    "arguments": {
      "token": "eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0In0.sig"
    }
  }
}

Response

result

{
  "header": { "alg": "HS256" },
  "payload": { "sub": "1234" },
  "expiresAt": null,
  "issuedAt": null
}

Generate

hash_generate

Generate a cryptographic hash of the given text.

Parameters

Param	Type	Default	Description
input*	string	—	Text to hash
algorithm	enum	sha256	md5 \| sha1 \| sha256 \| sha384 \| sha512

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "hash_generate",
    "arguments": {
      "input": "hello",
      "algorithm": "sha256"
    }
  }
}

Response

result

2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b982

uuid_generate

Generate one or more random UUIDs (v4).

Parameters

Param	Type	Default	Description
count	integer	1	How many UUIDs to generate (1–1000)
uppercase	boolean	false	Return uppercase UUIDs

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "uuid_generate",
    "arguments": {
      "count": 2
    }
  }
}

Response

result

c4fb1c02-6005-412f-9763-c1692566311d
ef797f7b-c205-4f68-80f7-67a6d3bfd57e

password_generate

Generate a strong random password with configurable character sets.

Parameters

Param	Type	Default	Description
length	integer	16	Password length (4–256)
uppercase	boolean	true	Include A–Z
lowercase	boolean	true	Include a–z
numbers	boolean	true	Include 0–9
symbols	boolean	true	Include !@#$%^&* etc.
excludeAmbiguous	boolean	false	Exclude 0, O, l, 1, I

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "password_generate",
    "arguments": {
      "length": 20
    }
  }
}

Response

result

xQ8!kLp2$mZr9@wTv3Nb

Convert

yaml_to_json

Convert YAML to JSON.

Parameters

Param	Type	Default	Description
yaml*	string	—	YAML source

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "yaml_to_json",
    "arguments": {
      "yaml": "a: 1\nb:\n  - x\n  - y"
    }
  }
}

Response

result

{
  "a": 1,
  "b": ["x", "y"]
}

json_to_yaml

Convert JSON to YAML.

Parameters

Param	Type	Default	Description
json*	string	—	JSON source

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "json_to_yaml",
    "arguments": {
      "json": "{\"a\":1,\"b\":[\"x\",\"y\"]}"
    }
  }
}

Response

result

a: 1
b:
  - x
  - y

json_to_csv

Convert a JSON array of flat objects to CSV.

Parameters

Param	Type	Default	Description
json*	string	—	JSON array of flat objects

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "json_to_csv",
    "arguments": {
      "json": "[{\"a\":1,\"b\":\"x\"},{\"a\":2,\"b\":\"y,z\"}]"
    }
  }
}

Response

result

a,b
1,x
2,"y,z"

csv_to_json

Convert CSV (with header row) to a JSON array of objects.

Parameters

Param	Type	Default	Description
csv*	string	—	CSV source, first row is the header

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "csv_to_json",
    "arguments": {
      "csv": "a,b\n1,x\n2,\"y,z\""
    }
  }
}

Response

result

[
  { "a": "1", "b": "x" },
  { "a": "2", "b": "y,z" }
]

timestamp_convert

Convert between Unix epoch (seconds or ms) and a human-readable date, or get the current time.

Parameters

Param	Type	Default	Description
input	string	—	Epoch or parseable date string. Omit for "now".

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "timestamp_convert",
    "arguments": {
      "input": "1700000000"
    }
  }
}

Response

result

{
  "iso": "2023-11-14T22:13:20.000Z",
  "utc": "Tue, 14 Nov 2023 22:13:20 GMT",
  "epochSeconds": 1700000000,
  "epochMillis": 1700000000000
}

color_convert

Convert a color between HEX, RGB, and HSL.

Parameters

Param	Type	Default	Description
color*	string	—	HEX (#rrggbb), rgb(r,g,b), or hsl(h,s%,l%)

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "color_convert",
    "arguments": {
      "color": "#6366f1"
    }
  }
}

Response

result

{
  "hex": "#6366f1",
  "rgb": "rgb(99, 102, 241)",
  "hsl": "hsl(239, 84%, 67%)"
}

Text & Regex

regex_test

Test a regular expression against text and return all matches with capture groups and indices.

Parameters

Param	Type	Default	Description
pattern*	string	—	Regex pattern, without slashes
flags	string	g	Regex flags, e.g. 'gi'
input*	string	—	Text to test against

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "regex_test",
    "arguments": {
      "pattern": "(\\w+)@(\\w+)",
      "input": "a@b c@d"
    }
  }
}

Response

result

{
  "matchCount": 2,
  "matches": [
    { "match": "a@b", "index": 0, "groups": ["a", "b"] },
    { "match": "c@d", "index": 4, "groups": ["c", "d"] }
  ]
}

text_diff

Compute a diff between two texts, line- or word-based.

Parameters

Param	Type	Default	Description
before*	string	—	Original text
after*	string	—	Modified text
mode	enum	line	line \| word

Request

tools/call

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "text_diff",
    "arguments": {
      "before": "hello world",
      "after": "hello there"
    }
  }
}

Response

result

- hello world
+ hello there

This is the free tier — deterministic tools, no external API calls, no data retention. Premium AI-powered tools (natural-language → regex/SQL, debug assistant) are planned behind an API key on the same MCP endpoint.