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

With no annotations, the description carries the burden of behavioral disclosure. It mentions the inclusion of a web_url with the calculation prefilled, which is a useful behavioral trait, but it does not specify the full return format (e.g., whether the numeric RPM is also returned) or any other side effects. It is adequate but incomplete for a tool with no annotation support.

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 two sentences, front-loading the core purpose and formula, and includes the essential unit distinctions. No filler or repetition; it earns its length.

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 tool is simple, but the absence of an output schema means the description should clarify what the caller receives. It mentions a web_url but does not confirm whether the numeric RPM is also returned or how the URL is used. For an agent to invoke and parse the result correctly, this is a notable gap.

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?

Schema coverage is 100%, so parameters are already well documented. The description adds the formulas and reinforces unit conventions (mm/inches, m/min/SFM), which is helpful but does not fundamentally expand beyond the schema. This matches the baseline of 3 for high coverage.

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 clearly states the tool calculates spindle speed (RPM) from cutting speed and provides the exact formulas. It distinguishes itself from sibling tools like cutting_speed_calculator by implying an inverse relationship, though it does not explicitly name alternatives.

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?

There is no guidance on when to use this tool versus alternatives such as cutting_speed_calculator or cnc_feeds_speeds. The description explains the math and units but does not state scenarios where this tool is the correct choice, leaving selection to inference.

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