Get Garmin sleep summaries

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

Annotations already cover the safety profile (readOnlyHint true, openWorldHint false), and the description adds genuinely non-obvious behavior: nights are keyed by wake-up date, the 7-night default, and Garmin's hard 31-night cap. It stops short of describing pagination or what happens if the range is exceeded, so it is strong but not exhaustive.

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?

Front-loaded with purpose and field inventory, then constraints, then the sibling pointer — no filler sentences. The metric list is dense but each item helps an agent judge fit, so it largely earns its space.

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?

With only two optional date parameters and no output schema, the description carries the full burden well: it enumerates return fields including the summary aggregates, states the defaults and hard limit, and clarifies date semantics. Nothing an agent needs to call this correctly is missing.

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%, so the baseline is 3, but the description adds interpretive value beyond the schema by explaining that the wake-up date is the key, which changes how start_date/end_date map to sleep nights. The 31-night cap is repeated from the schema, so it earns no extra credit there.

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 verb and resource ('Sleep per night over a date range') and enumerates the returned metrics, so an agent knows exactly what data it gets. It also distinguishes itself from the sibling garmin_get_sleep by scope (multi-night trends vs one night in full detail).

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 frames the use case ('for trends'), names the alternative for a different need ('For one night in full detail use garmin_get_sleep'), and gives the operating envelope: defaults to the last 7 nights, at most 31 nights per call. When-to-use, when-not, and the alternative are all present.

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