Calculator MCP Server

square_root

Calculates the principal square root of a non-negative number, returning an error if the input is negative.

Instructions

Compute the square root of a number.

Args: value: The number to take the square root of. Must be non-negative.

Returns: A string with the square root of value, or an error message if value is negative.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "value": "<value>"
    },
    "name": "square_root"
  }
}

Input Schema

Name	Required	Description	Default
`value`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 8, 2026

TDQS

A4.5/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. It discloses that the return is a string, and that an error message is returned for negative input. This is transparent about the error handling and output format. Lacks detail on precision or rounding, but for a simple operation this is sufficient.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Concise, well-structured with Args and Returns sections. No unnecessary words. Front-loaded purpose.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter math function, the description covers purpose, parameter constraint, and return behavior including errors. The output schema exists (per context), so the description need not explain return values in detail, but it does anyway. It could mention formatting but not critical.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema has zero description coverage, so the description compensates by explaining the parameter 'value' and its constraint (non-negative). This adds critical semantic meaning beyond the schema type.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: 'Compute the square root of a number.' Distinguishes from sibling arithmetic operations like add, subtract, etc. Clear and unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Does not explicitly contrast with siblings, but the operation is self-explanatory as a distinct math function. Provides no explicit when-to-use guidance, but implies usage for square root calculations. Slight gap: no mention of alternatives for other operations, but that's obvious given the tool name and description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server