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

Beyond the readOnlyHint/openWorldHint annotations, the description discloses critical behaviors: bare numbers are refused rather than guessed, all standard BMR formulas are returned along with the spread, and the response includes a medical disclaimer. It also instructs the agent not to relay a single calorie figure as exact.

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 essential information is front-loaded: what is computed and the mandatory-unit rule come first. The 'WHY DELEGATE THIS' section is somewhat redundant with the opening paragraph, but it earns some value by reinforcing the failure modes. Overall it is focused and well organized.

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 tool with no output schema, the description does a good job explaining the output philosophy: multiple formulas, spread as precision, and an embedded disclaimer. It could specify the exact return payload more concretely, but an agent has enough context to invoke the tool correctly and interpret results.

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 86%, which sets a solid baseline. The description adds meaning to height and weight by emphasizing that units are mandatory and explaining why unit mix-ups are dangerous. It does not need to repeat the schema's parameter details.

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 opens with a specific verb and resource: 'Compute BMI, energy expenditure, and protein targets from height and weight.' It also clarifies the unique output shape — every standard BMR formula plus the spread — which distinguishes it from generic calculator siblings.

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 'WHY DELEGATE THIS' section explicitly explains when the tool is the right choice: unit ambiguity and false precision. It also mentions the direct alternative (calling Body Metrics directly). It does not explicitly name sibling tools or state when not to use, but the guidance is otherwise clear.

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