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

With no annotations, the description carries the full burden and does well: it enumerates the returned quantities (units per layer, layers fitting height, volume-limited and payload-limited counts, binding constraint, utilisation) and discloses the fail-soft behavior when inputs are missing. It does not state assumptions such as weight distribution, palletisation, or whether the unit is stackable, which leaves some behavioral surface uncovered.

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?

Three sentences, front-loaded with the core question, then the return contents, then the input rule and failure mode. No filler, no repetition of the title, and each sentence carries distinct information.

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?

There is no output schema, so the description must describe returns – and it does so item by item, which is exactly what an agent needs. The only gap is that the optional parameters (maxLayers, allowRotation) are never mentioned in prose, though the schema covers them fully at 100% coverage.

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 100%, so the schema already documents all seven parameters including maxLayers and allowRotation. The description adds one genuinely useful clarification – the dimensions/weight are the packed size of a single unit – but says nothing about the optional layer cap or rotation flag, so it stays at the baseline for fully-covered schemas.

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?

States a specific verb (work out how many fit) plus the exact resource (flat-pack units or panels in a 20GP or 40HQ container), and scopes the calculation to a single unit's packed size. There are no siblings to distinguish from, and the purpose is unambiguous enough that an agent knows exactly what question this tool answers.

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?

Gives a concrete input precondition – 'Use the packed size and weight of ONE unit' – which prevents the common mistake of passing total shipment dimensions. It also defines the negative case (missing dimension/weight yields a report of what is missing, not a number). No alternatives or exclusions are named, but none exist for this tool.

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