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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered; the description nonetheless reinforces this with 'without authentication and does not read or save account data.' The genuinely additive content is the model-boundary disclosure that bars, bump stops, tires, and aero load are ignored, which tells the agent when this result will mislead. It does not mention numeric behavior such as rounding or unit echoes, but the output schema covers returns.

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?

Four short sentences, front-loaded with the purpose before the safety and limitation notes. 'Wheel rate compares spring changes' is the one soft sentence that restates the premise without adding information, keeping this just short of a 5.

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?

With a full output schema and complete annotations, the description does not need to explain return values or permissions. It covers purpose, output semantics ('wheel rate'), and the physical model's exclusions. The only gap is that it never signals the required spring angle or corner weight inputs, which an agent skimming the prose would not anticipate.

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 description coverage is 100%, and every parameter including springAngle, cornerWeight, and the unitSystem enum is documented inline, so the baseline of 3 applies. The description only names 'spring rate and motion ratio' and never mentions spring angle or corner weight, so it adds no meaning beyond the schema and is actually narrower than the required parameter set.

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?

States a specific verb and transformation: converts spring rate and motion ratio into wheel rate. The physics scope is unambiguous and clearly distinct from siblings like calculate_corner_balance or calculate_brake_bias. It stops short of naming the sibling it supersedes for a given question, so it lands at 4 rather than 5.

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?

'For setup comparisons' and 'Wheel rate compares spring changes' imply the use case, and the closing sentence excludes bars, bump stops, tires, and aero load from scope. However, no sibling alternative is named and no explicit when-not condition routes the agent elsewhere, so the guidance is implied rather than stated.

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