garmin_hrv

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

The read-only, idempotent, non-destructive annotations already establish the safety profile, and the description is consistent with them. It adds useful semantic context about what is read (overnight HRV, baseline, status, optional readings), but does not expand on behavior such as handling missing data or response shape beyond what the output schema provides.

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 definition is a single front-loaded sentence with no wasted words. The purpose, units, and optional samples behavior are all stated efficiently.

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 is simple, has rich annotations, and includes an output schema, so the description is adequate for basic selection. However, the missing explanation of the required 'day' parameter and the lack of usage guidance leave gaps for an agent deciding how to invoke it correctly.

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 carry parameter meaning. It explains the optional 'include_samples' behavior ('optionally include readings') but leaves the required 'day' parameter unexplained, including its date format and whether it selects the overnight period.

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 gives a specific verb ('Read') and resource ('overnight HRV'), plus units and returned components ('baseline and status'). It clearly states what the tool does, though it does not distinguish itself from sibling health tools like garmin_sleep or garmin_daily_metrics.

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?

There is no explicit guidance on when to use this tool versus alternatives, nor any prerequisites or exclusions. The only implied usage is reading overnight HRV, with no instructions about which sibling to choose for related metrics.

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