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

Annotations already declare the full safety profile (readOnlyHint=true, idempotentHint=true, openWorldHint=false, destructiveHint=false), so the safety burden is covered. The description adds nothing beyond that, and its 'Returns: {risk_threshold, cardiovascular_risk}' line duplicates the output schema rather than disclosing how risk is classified (e.g. sex-specific WHO thresholds).

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?

Two short sentences, front-loaded with the core purpose. The returns clause is slightly wasteful given an output schema exists, but nothing else is padded.

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?

An output schema exists so return values need no elaboration, all three parameters are fully documented in the schema, and annotations cover safety. The only meaningful omission is the basis for the risk classification, which is minor for a simple calculator.

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% — waist_cm, hip_cm and the sex enum are all documented in the schema itself. The description adds no units, ranges, or meaning beyond what the schema provides, so the baseline 3 applies.

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 names a specific verb and resource ('Calculate waist-to-hip ratio') plus the derived output ('cardiovascular risk level'), which is unambiguous. It does not, however, distinguish itself from the hundreds of sibling health calculators (e.g. calculate_body_fat, calculate_bmi) beyond the 'sante' bundle hint, so sibling differentiation is only indirect.

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 routing guidance is 'See list_bundles for related sante calculators,' which points to a catalog rather than telling the agent when this tool is the right choice versus calculate_bmi or calculate_body_fat. No when-not-to-use conditions or prerequisites are stated.

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