get_fitness

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that some metrics are latest/date-agnostic while others apply over a date range, but it does not cover permissions, read-only behavior, or return format.

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 short, front-loaded, and every phrase contributes to explaining the available metrics and their date behavior. There is no redundant or filler text.

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?

Given the detailed input schema and absence of output schema, the description provides enough context to call the tool correctly by metric name. It could go further in explaining return structure or read-only safety, but the core information needed for invocation is present.

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%, so the schema already documents the parameters. The description adds value by grouping the enum values into date-agnostic metrics and date-range metrics, which is semantic information not present in the schema itself.

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 identifies the resource as fitness/performance metrics and enumerates the specific metrics available. It distinguishes metric types by date behavior, but it does not explicitly differentiate this tool from siblings such as get_training or get_daily_health.

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 explains how to select metrics via the `metrics` parameter and which metrics are date-agnostic versus date-range based. However, it does not state when to use get_fitness instead of related sibling tools or provide exclusions.

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