garmin_body_battery

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering that this is a read operation with external data. The description adds the behavioral detail that it returns per-day charge and drain over a range, which is useful but does not disclose potential delays, auth requirements, or rate limits. No contradiction with 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?

The description is a single concise sentence that front-loads the core purpose and default behavior. Every word earns its place, with no redundant or vague phrasing.

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 (two optional params) and has an output schema, so return values need not be described. However, the description omits practical details like date format and the exact meaning of 'charge and drain per day' (e.g., units or aggregation). For a straightforward data-retrieval tool, this is adequate but leaves minor 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 description coverage is 0%, so the description must compensate for the lack of parameter documentation. It only mentions 'date range' and a default of 7 days, but does not specify date format, inclusivity, or how start/end relate to the range. This is insufficient for an agent to construct correct arguments without additional inference.

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 resource (Body Battery), the action (charge and drain per day), and the scope (date range with default last 7 days). It is specific and distinct from sibling tools like sleep or heart rate, so an agent can immediately identify what this tool provides.

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 implies usage for retrieving Body Battery data over a date range, and the default of 7 days gives a hint. However, it does not explicitly state when to use this over alternatives (e.g., garmin_daily_summary) or when not to use it. The guidance is implied rather than explicit.

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