Get Garmin Body Battery

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

Annotations already declare a read-only, closed-world operation, and the description adds substantive context beyond that: the default last-7-days window, the 31-day hard limit per call, the contents of the response, and the 30-minute averaging granularity when include_samples is set. What's missing is pagination/throttling behaviour and whether partial data is returned for days without a device sync, which matters for a health-data range query.

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?

Three sentences with no filler: payload definition first, the one optional flag next, then the routing alternative and the range constraints. Front-loaded with the resource and its scope, so an agent can decide quickly.

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?

No output schema exists, and the description compensates fully by enumerating the returned fields (event type, start time, duration, impact, Garmin feedback) and the charge/drain framing. Combined with the annotations and the fully documented schema, nothing material is missing for correct invocation.

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%, so all three parameters are already documented, and the description largely restates the schema: include_samples as "level through the day (averaged per 30 min)", the 7-day default, the 31-day cap. The added value is modest interpretation of what a sample represents, but no time-zone, boundary, or format guidance beyond what the schema already says.

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?

States a specific resource and scope ("Body Battery per day over a date range") plus the exact payload the tool returns: charge/drain totals and per-event breakdowns for sleep, activities, rest and stress periods. It explicitly names the sibling garmin_get_daily_summaries as the tool for daily max/min, so an agent can distinguish the two without opening either schema.

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?

Gives a concrete routing rule ("For daily max / min Body Battery use garmin_get_daily_summaries") and states the default window and the 31-day cap, which shapes how the agent should fill the date range. It stops short of addressing overlap with garmin_get_stress or garmin_get_sleep, which also surface stress/sleep data and could confuse selection.

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