Bearing Life

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

Annotations provide readOnlyHint=true, but the description goes beyond by detailing the calculation method (ISO 281 formula), the input modes (direct C or catalog lookup), and the output structure (including pass/fail against target_hours). It also discloses the exponent values for ball vs roller, which is behavioral detail not in annotations.

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 dense but efficient, fit in two sentences. It front-loads the core formula, then expands on input options and output fields. Every clause adds value, no filler.

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?

Given the tool's moderate complexity (6 params, no output schema), the description covers the formula, input modes, catalog lookup, and key outputs. It does not detail the full output dictionary (e.g., units of dynamic_load_c_n are implicit as N), but the essentials are covered. The absence of output schema makes it important to mention the return fields, which it does.

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 0%, so the description must compensate. It explains the meaning of dynamic_load_c_n, designation, and how they relate (e.g., '6205' -> C=14 kN). It also clarifies equivalent_load_p_n and speed_rpm are required, and kind affects the exponent. This adds substantial meaning beyond the bare parameter names.

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 purpose: compute basic rating life L10 per ISO 281, with formula and parameters. It distinguishes its function from siblings by specifying the output fields and the catalog lookup feature for deep-groove ball bearings. The verb 'calculate' is implicit but the resource (bearing life) and the specific method are explicit.

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 description explains how to supply the dynamic rating C or pull it from the catalog by designation, which is clear usage context. However, it does not explicitly state when to use this tool versus alternatives like 'belt_drive' or 'gear_rating', though the sibling list shows it is one of many mechanical calculation tools. The context is clear, but no exclusion criteria for other tools.

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