get_resting_heart_rate

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

With no annotations, the description carries the full burden. It does state the tool returns daily resting heart rate, which is a read-only behavior, but it does not describe response details, potential error conditions, or any limitations. For a simple getter this is acceptable, but it adds nothing beyond the tool's core function.

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 a single concise sentence, front-loaded with the verb and resource, and contains no wasted words. It is appropriately sized for the tool's simplicity.

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?

The tool has one optional parameter and an output schema, so the description is nearly complete. However, it does not explain the difference from get_heart_rate, and it leaves ambiguity about the nature of 'daily' data (e.g., array of daily values or an average). For a simple tool, this is adequate but with clear gaps.

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 links 'days' to 'requested number of days', which adds some clarity, but it is vague about whether days means calendar days, business days, or how the range ends. The enum values provide concrete options but the description does not enrich them.

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 action ('Get') and the resource ('daily resting heart rate'), and specifies the temporal scope ('for the requested number of days'). This distinguishes it from siblings like get_heart_rate and get_hrv, as it specifically targets resting heart rate over a period.

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 use when daily resting heart rate data is needed, but it does not explicitly mention when to prefer this over alternatives like get_heart_rate or get_hrv. No exclusions or alternative guidance are provided.

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