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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is fully covered. The description adds useful context about the metrics it computes, but does not disclose calculation assumptions (e.g., volumetric divisors), input constraints, or return format; with annotations carrying the safety burden, this is a moderate addition.

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?

A single front-loaded sentence with a colon that lists inputs first and outputs second. Every word earns its place and nothing is wasted.

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 read-only calculation tool with no output schema, the description does list the returned metrics, which helps an agent understand what to expect. It is only missing calculation assumptions (e.g., volumetric weight divisors) and the precise response shape, which are minor given the tool's self-contained nature.

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?

The description names the input categories (carton sizes, quantities, gross weights) but does not explain the nested array structure, optional gross_weight_kg, or units beyond what the schema field names already convey. With low schema description coverage, the description only partially compensates.

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 precisely what the tool computes from carton sizes, quantities, and gross weights: total CBM, gross weight, volumetric/chargeable weights, LCL revenue tons, and container fit. This is a specific verb-resource pairing (calculate shipment metrics) that is clearly distinct from the sibling tools create_trade_documents and lookup_hs_code.

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 provides no explicit when-to-use guidance, prerequisites, or alternatives. It implies usage only through the list of inputs and outputs, leaving the agent to infer the context on its own.

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