Calcport

io.github.CloudCorpRecordsPublished by GitHub account CloudCorpRecordsv0.1.0Updated Oct 29, 2026

Safe arithmetic: evaluate expressions and add, subtract, multiply, divide.

VerifiedSTDIODesktop onlyDeveloper Tools

Overview

AI-generated overview

Calcport is a local MCP server that gives an assistant safe arithmetic: one expression evaluator plus add, subtract, multiply and divide tools.

What you can do
  • Evaluate an expression with operators, parentheses, sqrt, abs, floor, ceil, round, pi and e
  • Add two numbers
  • Subtract one number from another
  • Multiply two numbers
  • Divide one number by another, with division by zero reported as an error
When to use it
Useful when you want an assistant to do exact arithmetic or check calculations without relying on its own mental math, and you prefer a tiny, sandboxed evaluator over a general code-execution tool.
Requirements
Runs as a local process over stdio, started with npx from the npm package or with docker from the container image. No accounts, API keys, environment variables or headers are declared, and no network access is needed at runtime.
Before you install
The tools only compute numbers and return results; nothing is written, sent or deleted. The evaluator is a hand-written parser limited to arithmetic, so it cannot run code, shell commands or property lookups.

Installation

In SourceWeft

  1. Open Calcport in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

calcport

calcport does arithmetic safely. Its centrepiece is an expression evaluator that understands the usual operators, parentheses, a handful of functions, and the constants pi and e — and nothing else. The evaluator is a hand-written parser, so an expression can never turn into code execution, a shell call, or a property lookup. Around it sit four single-purpose operations for callers that just need one sum, difference, product, or quotient.

Install

bash
npx @reneturcios/calcport calculate "2+3*4"

Or run the container image:

bash
docker run -i ghcr.io/cloudcorprecords/calcport

The container defaults to the MCP server (see below). Pass CLI arguments to use it as a CLI instead.

CLI

bash
# Evaluate an expressioncalcport calculate "sqrt(3^2 + 4^2) + pi"# 8.141592653589793
# Single operationscalcport add 2 3          # 5calcport subtract 10 4    # 6calcport multiply 2.5 4   # 10calcport divide 7 2       # 3.5
# Machine-readable outputcalcport calculate "2^10" --jsoncalcport add 2 3 --json
calcport --version

Expressions may use + - * / % ^, parentheses, unary minus, the functions sqrt, abs, floor, ceil, and round, and the constants pi and e. ^ is right-associative, so 2^3^2 is 512.

Exit codes: 0 on success, 1 when a calculation cannot be done (division by zero, a malformed expression — the error says why), 2 for usage errors.

MCP server

One bin serves both faces. The mcp subcommand starts a stdio MCP server:

bash
npx -y @reneturcios/calcport mcp

MCP client configuration:

json
{  "mcpServers": {    "calcport": {      "command": "npx",      "args": ["-y", "@reneturcios/calcport", "mcp"]    }  }}

Tools

ToolInputWhat it returns
calculateexpression (string, required)The numeric result of the expression, with the expression echoed back.
adda, b (numbers, required)a + b, with both operands.
subtracta, b (numbers, required)a - b, with both operands.
multiplya, b (numbers, required)a * b, with both operands.
dividea, b (numbers, required)a / b, with both operands. Dividing by zero is an error.

Development

bash
npm installnpm run build   # tsc -> dist/npm test        # node test runner over test/*.test.ts, no networknpm run dev     # run the CLI from source via tsx

License

MIT — see LICENSE.

Source: README.md at commit b3087c2

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.1.0LatestOct 29, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts