get_recovery_metrics

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

The description discloses the output metrics and date format, but since no annotations are present, it carries the full burden. It does not mention side effects, authentication, or error handling, which is acceptable for a simple read operation.

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 with two sentences that cover purpose, parameters, and usage. Every sentence adds value with no wasted words.

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 description covers the input format, default, and output metrics. For a simple tool with one parameter and no output schema, this is mostly complete. It lacks details on response structure or data availability, but these are minor gaps.

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 parameter has no description, but the description adds meaning by specifying the date format (YYYY-MM-DD) and default value (today). This fully compensates for the 0% schema coverage.

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 it retrieves recovery metrics (sleep, Body Battery, HRV, resting heart rate) for a single day, which distinguishes it from sibling tools like get_daily_summary. The specific verb and resource are well-defined.

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 one usage guideline: call multiple times for multiple days. However, it does not compare to sibling tools like get_daily_summary or specify when to prefer this tool over alternatives.

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