get_body_composition

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

With no annotations, the description carries the full burden of explaining behavior. It discloses that the tool returns weight, body fat %, muscle mass, bone mass, and body water %, which is useful. It does not mention potential edge cases like missing data, inclusive/exclusive date boundaries, or any side effects, though the operation appears to be a read-only query.

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 two concise sentences with no filler. The purpose and date format are stated first, followed by the returned metrics, each sentence earning its place.

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 simple retrieval tool, the description covers the core purpose, parameters' format, and returned data. An output schema exists, so the return structure is additionally specified. It could be more complete with details on end_date default behavior or units, but it is sufficient for basic invocation.

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 must compensate. It adds the date format requirement 'YYYY-MM-DD' and clarifies that the parameters define a date range. It does not explain the default/nullable behavior of end_date or whether the range is inclusive, but the parameter names are self-explanatory.

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 clearly identifies the tool's action ('Get body composition data') and resource (body composition metrics for a date range). It lists the specific returned metrics, which helps distinguish it from sibling tools like get_weight. However, it does not explicitly contrast itself with overlapping siblings beyond listing its own outputs.

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 description implies the tool is for retrieving body composition data over a date range, providing a clear usage context. It does not name alternatives or state when not to use it, leaving the agent to infer selection from the sibling tool names and outputs.

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