Get HRV summaries

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered; the description adds real value by disclosing the return payload and the default 7-day-ending-today window. It says nothing about pagination, per-day gaps, or how Garmin's feedback/status is represented when a night is missing.

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?

Two sentences, zero filler: the return shape is front-loaded and the parameter format follows. Every clause (inclusive bounds, default window) conveys information the agent cannot get elsewhere.

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 no output schema and 0% schema coverage, the description must explain both the payload and the parameters, and it does so adequately for a read-only two-param tool. The missing piece is sibling disambiguation from garmin_get_hrv, which is the main risk of a mis-invocation in this tool family.

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 0% and both parameters are bare nullable strings, so the description carries the full burden — and it does: it gives the YYYY-MM-DD format, states that the bounds are inclusive, and specifies the default window. Only timezone handling is left unstated, which keeps it short of a 5.

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?

Names a specific resource (nightly HRV summaries over a date range) and enumerates exactly what each entry contains: last-night average, weekly average, baseline band, status, and Garmin's feedback. An agent knows precisely what data comes back, though the description never distinguishes this from the sibling garmin_get_hrv.

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?

There is no statement of when to reach for this versus garmin_get_hrv, garmin_get_daily_summaries, or garmin_get_sleep_summaries — all plausible alternatives in a 24-tool list. The only usage-adjacent information is the default date window, which describes fallback behavior rather than selection criteria.

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