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

Annotations already cover safety (readOnlyHint, destructiveHint=false, openWorldHint=false), so the bar is lower; the description adds real context the annotations do not — no authentication required, no account data read or saved, and a caveat that tire growth and converter/clutch slip affect real-world accuracy. That accuracy caveat is exactly the kind of behavioral note that earns credit.

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 sentences, front-loaded with the core computation before auth and caveats. Efficient and well ordered, with only mild overlap between the first and third sentences.

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?

An output schema exists, so return values need no explanation, and the description still covers purpose, key inputs, auth/data behavior, and accuracy limits. Complete enough to invoke correctly, short only of explicit sibling differentiation.

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 the baseline is 3, but the description adds meaning beyond the schema: it ties the output to 'shift drop' (the nextGear parameter) and advises using a measured tire diameter rather than a nominal one. This nudges it above baseline without fully documenting the enum or unit parameters.

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?

Specific verb and multiple concrete outputs ('Check speed, RPM, and shift drop') plus the required inputs (tire size, final drive, gear ratio). The resource is distinct from calculation siblings like calculate_brake_bias or calculate_corner_balance, though the description never names or contrasts a sibling explicitly, keeping it at a 4.

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?

'Use measured tire diameter when possible' gives a genuine input-selection hint, but there is no explicit when-to-use/when-not framing and no alternative tool named. Usage is implied by the purpose statement rather than stated.

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