unit_converter

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

Beyond the readOnly and idempotent annotations, the description discloses deterministic behavior, formula naming in responses, cross-dimension error behavior with accepted-unit lists, rate limits with retry headers, and specific unit definitions such as IATA divisor, short ton, and long ton. This gives the agent essential runtime expectations.

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 every sentence earns its place: unit inventory, special freight targets, behavior, error handling, rate limiting, return envelope, and sibling-tool routing. It is long because the tool genuinely has multiple behaviors to document, and there is 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?

For a tool with dimensional restrictions, freight-specific targets, rate limiting, error bodies, and a defined response envelope, the description covers all these aspects without missing any critical context. It even explains when to use sibling tools first, making it effectively self-contained.

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 significant meaning: category groupings for units, the IATA 6,000 divisor making 1 CBM = 166.67 kg, the sea W/M freight tonne rule, and the exact difference between tonnes, short tons, and long tons. This goes well beyond the enum lists in the schema.

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 and resource: converting freight and logistics units across weight, volume, and length dimensions, with two freight-specific targets. It distinguishes itself from sibling calculators by naming cbm_calculator and chargeable_weight_calculator as related but different tools.

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?

It explicitly gives usage context: dimensions must match, freight targets are only valid from cbm, and it names alternatives — cbm_calculator for dimension-to-volume conversion and chargeable_weight_calculator for proper air billing with pieces and a custom divisor. It also advises retry behavior on 429 and directing users to get_subscribe_link for higher limits.

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