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

Annotations already declare readOnlyHint, idempotentHint, non-destructive behavior, and a closed-world context. The description adds that it estimates a body condition score proxy and returns thresholds, but does not disclose calculation limitations, assumptions, or interpretation guidance beyond the annotations.

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 short and front-loaded with the core purpose. However, 'Returns: {thresholds}' reads like a placeholder, especially since an output schema already exists, and the list_bundles pointer is only marginally useful.

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 tool is a simple three-parameter calculator with an output schema and safety annotations, so the core description is adequate. Still, the lack of parameter semantics and explicit sibling routing leaves meaningful gaps for an agent selecting and invoking it 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 description coverage is 0%, so the description should carry more parameter meaning. It clarifies the animal scope as dogs/cats, but does not explain weight_kg, body_length_cm, how body length should be measured, or how the inputs affect the BMI proxy.

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: estimate body condition score proxy (BMI) for dogs and cats. It clearly distinguishes this from generic BMI or pet-age/food calculators by scoping it to dogs and cats and to body condition.

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 only guidance is a pointer to list_bundles for related 'animaux' calculators, which does not explain when to use this tool instead of siblings such as calculate_bmi, calculate_pet_food_portion, or calculate_dog_age. The dog/cat scope is implied, but there are no explicit when/when-not conditions or alternatives.

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