ldm_calculator

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

Annotations already mark readOnlyHint, idempotentHint, and destructiveHint=false, but the description adds substantial behavioral detail: deterministic behavior, stackable=true dividing floor footprint, fits checking against vehicle length, weight_kg enabling payload checks, and rate limiting with 429 error and retry_after_seconds. It also discloses the deprecated rigid10 vehicle and advisory warnings.

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 well organized: definition, input rule, behavior, rate limit, return envelope, and related tools. Every sentence adds value without redundancy against the schema, and the structure front-loads the core concept before diving into details.

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 9-parameter calculator with an output schema, the description covers all necessary context: input modes, behavioral rules, error handling with rate limits, return structure (ldm, vehicle, utilisation_percent, pallet_spaces, total_weight_kg, fits, warnings, confidence, _source, citation), and related tools. This is sufficient for an agent to select and invoke the tool correctly.

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 coverage is 100%, but the description enriches parameter meaning beyond the schema: it explains pallet preset dimensions, US vs EU width conventions, stackable/stack_height impact on footprint, and that utilisation_percent is based on vehicle length. This goes far beyond the baseline of simply restating parameter descriptions.

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 begins with a specific action and resource: 'Calculate loading metres (LDM) for European road freight — how much trailer length a pallet load occupies.' It distinguishes itself from siblings by naming vehicle_lookup, pallet_fitting_calculator, and consignment_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 states the input requirement (pallet preset OR custom length_mm + width_mm) and warns that omitting both errors. It provides clear alternatives via the Related list, each with a parenthetical distinction (e.g., pallet_fitting_calculator for boxes onto one pallet), and explains when US vehicle presets differ from EU conventions.

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