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

With no annotations provided, the description carries the full burden of behavioral disclosure. It transparently states that the tool always returns the speed converted to the other unit system and that a pre-filled web_url is included. This exceeds what is visible in the schema and helps the agent anticipate output behavior.

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

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

The description is concise and front-loaded: it states the core calculation, gives formulas, notes the conversion behavior, and mentions the web_url in three efficient sentences. No filler or redundant restatement of parameter names.

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

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

The description explains the calculation and output behavior but does not fully specify the response structure. Since no output schema is present, the agent must infer the exact fields returned beyond the web_url and the converted speed, leaving some ambiguity for a tool with no output schema.

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

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

Although schema coverage is 100%, the description adds semantic value by defining the mathematical relationship between diameter (D) and spindle speed (n), clarifying how the parameters interact and how unit selection affects the formula. This goes beyond the schema's simple property descriptions.

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

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

The description states a specific verb-resource relationship: it calculates cutting speed from spindle speed using explicit formulas for both metric and imperial. This clearly distinguishes it from sibling tools like rpm_calculator, which would perform the inverse calculation.

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

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

The formula and 'Cutting speed from spindle speed' imply the use case: use when you know spindle speed and diameter. However, it does not explicitly state when not to use this tool or mention the sibling rpm_calculator as the alternative for the inverse calculation, so guidance is implied rather than explicit.

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