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

With no annotations, the description carries the full burden and does disclose meaningful behavior: the estimate is planning-only rather than a binding quote, it is derived from Freightos public LCL as a container index, Brent crude for bunker, and Joint War Committee listed areas, and certain countries are refused outright. It does not state whether the result is a range, its precision, or any latency/caching behavior.

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, purpose front-loaded, then sourcing, then the disclaimer, then the refusal list. No filler and nothing repeated from structured fields.

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?

The behavioral side is reasonably covered, but for a 5-parameter tool with 20% schema coverage, no annotations, and no output schema, the description leaves the caller guessing about mode, vehicleClass, and what the returned estimate looks like. Adequate but with clear gaps.

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 only 20% (just countryCode), and the description does not explain any parameter. 'Japan load port' loosely maps to the origin enum and 'destination' to countryCode/port, but mode and vehicleClass — both enum-typed and central to an estimate — are entirely undocumented in either place.

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 — producing a planning ocean-freight estimate from a Japan load port to a destination — which is unambiguous and clearly distinct from every sibling (get_import_guide, list_destinations, get_vehicle, etc.). It stops short of explicitly naming a sibling it is not, but the domain is narrow enough that confusion is unlikely.

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 provides a clear exclusion ('Not a booking quote') and a hard restriction ('Iran and Russia are refused'), which tells the agent when this tool is inappropriate. It does not name an alternative tool to use instead for an actual booking quote, so the when-not is stated without a when-instead.

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