Zero-dependency scientific calculator MCP server with strict validation, worker isolation, and 43 tools across 8 categories
Connect Cruncher MCP to Claude, Cursor or any other MCP client and it stops being a tab you switch to. Zero-dependency scientific calculator MCP server with strict validation, worker isolation, and 43 tools across 8 categories. The cruncher mcp mcp server is what makes that connection.
A powerful scientific calculator for your AI assistant, built as a Model Context Protocol (MCP) server. Cruncher allows compatible AI clients (like Claude Desktop) to perform complex mathematical calculations, handle memory, perform statistical analysis, and access scientific constants with a simple, secure, and standardized interface.
The Model Context Protocol (MCP) is an open standard that allows AI applications to securely connect with external data sources and tools. Think of it as a universal API for AI. By implementing Cruncher as an MCP server, any AI that understands MCP can instantly gain powerful, built-in calculator capabilities without custom integrations.
The toolset is worth reading before you wire it up, because it tells you what the integration is really for:
evaluate_expression — Evaluates a plain text math expression (e.g. (5 + 3) * 10 / 2)add — Adds two numbers (a + b)subtract — Subtracts the second number from the first (a - b)multiply — Multiplies two numbers (a * b)divide — Divides the first number by the second (a / b)modulo — Calculates the remainder (a mod b)power — Calculates a raised to the power of b (a^b)sqrt — Calculates the square root of a valuefactorial — Calculates the factorial of a non-negative integer (n!)convert_unit — Convert between common units. 8 categories, 80+ unitsconvert_base — Converts between bases 2, 8, 10, 16Trigonometry — The Trigonometry tool exposed by this serverConfiguration is passed through the environment: CRUNCHER_TOOL_SET. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.
The server ships on npm as @slbdn/cruncher-mcp, so your MCP client can launch it on demand — there is no separate build step. Add the server block to your client's configuration, restart it, and the tools register themselves.
Plenty of developer tooling servers cover similar ground. The differences that matter in practice are scope of access and how much setup stands between you and a working tool call. Cruncher MCP's toolset — evaluate_expression, add, subtract and 11 more — is a fair guide to whether it matches your workflow. It is maintained by islobodan; worth a glance at recent repository activity before you build anything load-bearing on it.
We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.
| Tool | What it does |
|---|---|
| evaluate_expression | Evaluates a plain text math expression (e.g. (5 + 3) * 10 / 2). |
| add | Adds two numbers (a + b). |
| subtract | Subtracts the second number from the first (a - b). |
| multiply | Multiplies two numbers (a * b). |
| divide | Divides the first number by the second (a / b). |
| modulo | Calculates the remainder (a mod b). |
| power | Calculates a raised to the power of b (a^b). |
| sqrt | Calculates the square root of a value. |
| factorial | Calculates the factorial of a non-negative integer (n!). |
| convert_unit | Convert between common units. 8 categories, 80+ units. |
| convert_base | Converts between bases 2, 8, 10, 16. |
| Trigonometry | The Trigonometry tool exposed by this server. |
| sine | Calculates the sine of an angle. |
| cosine | Calculates the cosine of an angle. |
{
"mcpServers": {
"cruncher": {
"command": "npx",
"args": ["-y", "@slbdn/cruncher-mcp"]
}
}
}Configuration as documented by the project. Restart the client after saving.
| Variable | Description | Required |
|---|---|---|
| CRUNCHER_TOOL_SET | Configuration value read at startup. | Optional |
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