Fetch WHOOP document

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

Annotations already declare readOnlyHint=true, so the description's job is to add context beyond that. It does so by specifying supported id forms (day, sleep, workout, etc.), but does not disclose error handling, permissions, or response behavior. The value added is moderate.

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?

The description consists of two short sentences with no extraneous information. It front-loads the core purpose and provides the critical id format details efficiently, earning each word's place.

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 an output schema available, the description does not need to explain return values. It sufficiently covers the tool's purpose, input, and usage context. Minor omission: no mention of prerequisites or error conditions, but for a simple fetch with readOnlyHint, this is nearly complete.

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?

Despite 0% schema description coverage, the description fully compensates by detailing all valid id formats: 'day:YYYY-MM-DD, sleep:<uuid>, workout:<uuid>, cycle:<int>, recovery:<cycle_int>, profile.' This adds crucial meaning beyond the schema's type 'string' alone.

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?

The description clearly states the tool fetches a full document for an id returned by `search`, with specific verb ('fetch') and resource ('WHOOP document'). It distinguishes itself by being a generic fetcher for any id, setting it apart from the many get_* sibling tools that target specific document types.

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?

The description provides context by saying to use ids from `search` and lists supported id formats, but it does not explicitly state when to use this tool versus alternatives like get_workout or get_sleep. No exclusions or when-not-to-use guidance is given, making it adequate but not explicit.

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