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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior. The description adds useful substantive context by saying what it returns (half their height and the suggested Indian range limit) and by excluding inappropriate populations.

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?

It is front-loaded with the use case, then examples, then return content, then exclusions. Every sentence serves a purpose and there is no filler.

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 four-parameter read-only calculator with no output schema, the description provides enough scope, output expectation, and exclusions for correct selection. It could be slightly richer on the feet/inches versus centimetres input path, but the schema handles that.

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 parameters are already documented in the schema, including the sex enum and height units. The description reinforces height-based calculation but adds no syntax or unit-selection guidance beyond the schema.

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 resource and output: waist-size target from height, returning half-height and a suggested Indian range limit. It does not distinguish this from the sibling waist_check, so it stops short of a 5.

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 gives clear when-to-use examples and explicit when-not-to-use exclusions for children, pregnancy, and medical questions. It does not name the sibling waist_check as an alternative, so it is not fully complete on alternatives.

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