get_heart_vitals

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

With no annotations provided, the description carries the transparency burden. It discloses behavior such as the default summary format (avg, min, max, trend, resting HR) and the availability of detailed timestamps. It does not mention rate limits or error scenarios, but adds meaningful behavioral context beyond the schema.

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 concise and well-structured: three sentences that front-load the purpose, then provide usage details. Every sentence contributes useful information without redundancy or unnecessary elaboration.

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 five parameters and no output schema, so the description needs to explain return values and parameter usage. It covers summary vs. detailed and last_minutes, but omits guidance on start_time, end_time, and date parameters, which could leave the agent uncertain about how to choose between time filters. 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 coverage is 100%, so the baseline is 3. The description adds value by explaining the default format, listing summary metrics, and giving a concrete example for last_minutes. This enhances understanding beyond the raw schema definitions.

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's function with a specific verb and resource: 'Get heart-related metrics including heart rate, HRV, and SpO2.' This distinguishes it from sibling tools focused on other health data like temperature or sleep. The scope is unambiguous.

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 clear context on how to use the tool, including default summary output, the detailed format option, and last_minutes filtering. It does not explicitly mention alternatives or exclusions, but the heart-specific focus implies when this tool should be used relative to siblings.

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