Get Garmin Body Battery

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive. The description adds the meaningful behavioral constraint of an inclusive range capped at 31 days, which is not covered by annotations. This is valuable additional context.

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, tightly-worded sentence that front-loads the tool's purpose and its most critical constraint. There is no filler or redundant information.

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-only tool with an output schema and safety annotations, the description covers the essential behavioral constraint (31-day inclusive range). Minor gaps like date format and null end_date handling are likely inferable from context or the schema, so overall it is adequate.

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?

With 0% schema description coverage, the description must clarify the parameters. It does so by specifying that the range is inclusive and at most 31 days, giving semantic meaning to start_date and end_date beyond the raw schema. However, it does not specify date format or behavior when end_date is null, leaving some ambiguity.

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 action ('Get'), the resource ('Body Battery reports'), and the key constraint ('inclusive range of at most 31 days'). This distinguishes it from sibling tools like get_heart_rate or get_sleep, making the purpose 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?

No guidance is given on when to use this tool versus alternatives. With many sibling get_* tools, an agent might benefit from knowing that this is the specific tool for Body Battery data, but the description lacks any comparison or exclusion criteria.

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