get_body_battery

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

Since no annotations are provided, the description carries full burden. It discloses that Body Battery is based on sleep, stress, and activity, and that it shows charged/drained periods and sleep quality impact. This adds useful context beyond a simple read operation, though it does not mention authentication or rate limits (which are minor for a read-only tool).

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 two sentences, front-loading the action and resource, then explaining the concept. No unnecessary words – every sentence adds value.

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 no output schema, but the description hints at output by mentioning 'charged/drained periods' and 'sleep quality impact' and the 0-100 scale. For a tool with two simple parameters, this provides adequate context for an agent to understand what the data represents.

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%, and the description only mentions 'date range' without adding details beyond what the schema provides (e.g., default behaviors). The schema already describes startDate defaulting to today and endDate defaulting to startDate, so the description adds no new parameter information. Baseline 3 is appropriate.

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 retrieves 'Body Battery energy level data for a date range' and explains that Body Battery tracks energy levels (0-100) based on sleep, stress, and activity. This effectively distinguishes it from sibling tools like get_sleep_data or get_hrv_data.

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 specifies usage 'for a date range' and explains the concept of Body Battery, but does not explicitly state when to use this tool versus alternatives like get_sleep_data or get_stress_data. The guidance is implied by the resource type but lacks explicit exclusions or alternative suggestions.

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