Recovery trends

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds real value beyond them: the response composition (status, flagged days, weekly averages, correlations with strength), the 180-day ceiling, and an honest statistical caveat about causation and noise. It stops short of describing pagination or how the 180-day limit is enforced when exceeded.

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 the core purpose in the first clause, then return contents, caveats, and limits in a logical order. Two compact paragraphs with no filler; only the causation caveat slightly overlaps the noise warning.

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, so the description carries the full burden of describing returns — and it does so concretely (status comparators, flagged days, weekly averages, correlation pairs). For a read-only analytics tool with a fully documented 3-parameter schema, nothing material 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 a baseline 3 applies, but the description genuinely adds meaning the schema lacks: the default range (last 8 weeks) and the maximum window (180 days), which govern how start_date/end_date should be chosen. The response_format enum is fully documented in the schema and needs no prose.

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?

Specific verb+resource: 'Relate training load to recovery markers, day by day' with the exact metrics enumerated (resting HR, HRV, sleep score/duration, Body Battery, stress). The rolling-baseline and correlation framing clearly separates it from point-query siblings like garmin_get_hrv, garmin_get_sleep, and garmin_get_daily_health without needing to name them.

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 clear operating context — defaults to the last 8 weeks, hard cap of 180 days, and warns that 'short periods give noisy results', which implicitly steers the agent toward longer windows. It does not explicitly say when to prefer point-query siblings over this trend view, so no exclusion guidance.

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