oura_rest_mode

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description doesn't need to restate safety. It adds context about what rest mode is (relaxes activity goals and readiness contributors), which is semantically useful but doesn't disclose additional behavioral traits such as pagination, rate limits, or response format. Given the annotations, this is adequate.

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 extremely concise—two short sentences plus a parameter line. The main purpose is front-loaded, and the additional clarification about rest mode is valuable without being verbose. No filler or redundancy.

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 is simple (one optional parameter) and has an output schema, so return-value details are likely covered there. The description provides the necessary context about the parameter format, default behavior, and the meaning of the data. It lacks explicit notes on edge cases (e.g., no rest periods on the date) but these are likely inferable. Slightly more detail could be added, but it's 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?

The schema only lists a 'date' parameter with a default of null and no description. The description adds critical semantics: it specifies the date format (YYYY-MM-DD) and that it defaults to today. Since schema description coverage is 0%, the description fully compensates for the parameter documentation gap.

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 states a specific verb ('Get') and resource ('rest mode periods'), and clarifies what rest mode means (illness/injury/recovery mode). This is distinct from sibling tools like oura_readiness or oura_sleep, and the phrasing makes the tool's scope obvious.

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 usage is implied by the resource name and description—if you need rest mode data, use this tool. However, there is no explicit guidance on when to prefer this over alternatives, nor are any sibling comparisons or exclusions mentioned. The context is clear but not elaborated.

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