get_sleep

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

No annotations are provided, so the description carries full burden for behavioral disclosure. It correctly states it is a read operation (no mutation implied) and discloses that data is per night (excludes naps). However, it does not mention pagination, rate limits, data freshness, or any auth requirements beyond what might be implicit, though none are needed given the tool's simplicity.

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 is concise (3 sentences) and front-loaded with the most important information (what data is returned). Every sentence adds value: first sentence specifies fields and excludes naps, second explains the two input modes, third states the use case and return format. Loses 1 point for including the e.g. inside the schema description rather than in the main description, but that's a minor issue.

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?

The tool has 3 parameters (all optional, no output schema) and no annotations, so the description needs to compensate for the missing output schema. It does well by stating the return format ('summary with averages plus nightly records'). It covers all input modes and use case. A 5 would require explicit disclaimer about max date range or mention of any data source limitations.

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 description coverage is 100%, so the parameters are already well-documented in the schema. The description adds value by explaining the two query modes ('last N days' vs 'explicit start/end range') and provides a concrete example of the start/end format, which goes beyond the schema's description. Baseline 3 is appropriate.

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 uses specific verbs ('Get') and clearly identifies the resource ('WHOOP sleep data'). It lists key fields (sleep performance %, efficiency %, time in bed, etc.) and distinguishes itself from other tools by explicitly noting it excludes naps, focusing on nightly data.

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 clearly states when to use this tool ('to answer questions about sleep quality or duration') and provides explicit guidance on using either 'last N days' or an explicit historical range, with a concrete example ('e.g. a specific past month'). It does not mention sibling tools for exclusion, but the specific verb+resource + listing of fields makes the differentiation clear.

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