get_rhr_day

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

The verb 'Get' implies a read-only operation, but with no annotations the description carries the full burden of explaining behavior. It does not state what is returned, whether any side effects occur, or how the response is structured, leaving the actual behavior under-specified.

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 free of irrelevant content, with the Args block clearly listing the parameter. It is not padded, though the first sentence is somewhat generic and could have been more specific without adding length.

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?

With no output schema and a large sibling list, the description leaves important context missing: it does not state what the returned resting heart rate data looks like, what units are used, or how this endpoint differs from the many other heart-rate and summary tools. The single date argument helps, but the overall contract is incomplete.

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?

The description adds the date format 'YYYY-MM-DD' beyond the raw schema, which is helpful for the single date parameter. However, it does not clarify the meaning of the date, timezone considerations, or any constraints such as valid ranges or historical limits.

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 the verb and resource, 'Get resting heart rate data,' but uses the vague term 'data' and does not explicitly mention the single-day scope that the tool name and date argument imply. It also lacks any differentiation from sibling tools like get_heart_rates or get_heart_rates_summary.

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 gives no guidance on when to use this tool instead of related heart-rate tools. There is no mention of scenarios, exclusions, or alternatives, so an agent cannot distinguish this endpoint from get_heart_rates, get_heart_rates_summary, or other cardiovascular endpoints.

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