Heart rate

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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds valuable behavioral context beyond this: it discloses the granularity of data (summary stats vs. continuous series) and warns that 'full' returns an 'accurate but potentially enormous' payload. No contradiction exists between description and annotations.

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?

Two sentences, front-loaded with the core purpose, followed by a parameter tip and a sibling-tool alternative. Every sentence earns its place with zero redundancy. Highly concise and well-structured.

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?

For a simple two-parameter read tool with rich annotations and thorough schema descriptions, the description provides enough context for correct selection and invocation. It explains what outputs to expect (resting, min/max, 7-day average), covers the full-detail option, and names the alternative for workout data. No output schema exists, but the description fills that gap adequately.

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 100%, and the schema already thoroughly explains both 'date' and 'detail' parameters, including defaults and trade-offs. The description only briefly mentions detail='full' for continuous series, which is already in the schema, adding no new parameter-level meaning. Baseline 3 applies because the schema carries the load.

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 verb ('Get'), resource ('heart rate'), and scope ('for one day') along with specific outputs (resting, min/max, 7-day average). It also distinguishes from the sibling tool garmin_get_activity by directing workout-specific heart rate queries there. This is a specific, actionable purpose statement.

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?

Explicitly says when to use this tool (for daily heart rate summary) and when not to (for workout-specific heart rate, use garmin_get_activity instead). Also provides guidance on the 'detail' parameter, recommending 'summary' for most cases and cautioning that 'full' is potentially enormous. This is excellent usage direction.

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