Daily overview

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds value beyond that by enumerating the returned content (HRV, resting HR, SpO2, skin temp, naps, strain) — important since there is no output schema — but says nothing about auth, rate limits, or missing-data behavior.

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, no waste, and the core purpose (full day aggregate) is front-loaded ahead of the parameter hint. Every clause earns its place by naming a returned data domain.

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?

For a single-optional-parameter, read-only aggregate tool with no output schema, the description supplies exactly what the agent needs: what comes back and how to default the date. Nothing required to invoke it 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% and the schema already documents the YYYY-MM-DD format and the default-to-latest behavior, so the description's date note is largely redundant with structured data. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb+resource (aggregated 'everything for one WHOOP day') and enumerates the exact domains returned: recovery, sleep, naps, strain/calories, workouts. This makes it clearly distinguishable from siblings like list_recoveries, list_sleeps, and get_workout, which each cover only one domain.

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 usage rule for the single parameter ('Omit date for the current/latest day'), which is the main decision an agent must make. It implies when to use this over the per-domain listers but never names an alternative tool explicitly, so it stops short of a 5.

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