get_heart_rate

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. It does not state whether the tool is read-only, requires authentication, has rate limits, or what happens if no data exists for the requested day. The description implies a safe read operation but does not confirm it.

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 front-loaded with the tool's output. Every sentence adds value, but the 'Args:' section is somewhat redundant with the schema, though it provides useful examples. Could be slightly tighter by integrating examples into the main text.

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?

Given the tool has an output schema, the description need not detail return fields, but it does list key returned metrics. However, it omits behavioral context (e.g., error handling, no-data cases) and usage guidance for alternative tools. Overall adequate for a simple retrieval tool but not fully comprehensive.

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 explain the parameter. It does this effectively by giving concrete example values for the 'day' parameter (today, yesterday, date format), adding meaning beyond the schema's default value.

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 states the tool returns heart rate data for one day, including resting, lowest, highest, and a seven-day average. This is specific and distinct from sibling tools like get_hrv, get_steps, or get_sleep, which focus on different health 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?

The description provides examples for the 'day' parameter ('today', 'yesterday', '2026-08-18'), which guides usage. However, it does not explicitly exclude cases where broader date ranges are needed (e.g., via get_date_range_summary) or clarify when not to use this tool versus alternatives.

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