get_athlete_stats

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

With no annotations, the description carries full burden. It discloses the return structure (time periods, sports, units) and implies a read-only operation. However, it does not mention authentication requirements or rate limits, which are common but not critical for this simple retrieval.

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 a single sentence followed by a bullet list of return fields. It is front-loaded with the purpose, uses clear units, and contains no redundant information.

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?

Despite lacking an output schema, the description fully explains return values: time ranges, sports, metrics, and units. It covers everything an agent needs to interpret the response correctly.

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 input schema has zero parameters, so schema description coverage is 100%. The description adds no parameter info but clarifies the output structure in detail, which is sufficient given no parameters exist.

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 verb 'Get' and resource 'aggregated activity statistics', specifies sports (ride/run/swim), time periods (recent 4 weeks, YTD, all-time), and metrics (count, distance, moving_time, elevation_gain). This distinguishes it from siblings like get_activity_detail or list_activities.

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 implies usage for aggregated stats but does not explicitly state when to use this tool versus alternatives like get_activity_detail (individual activity) or get_athlete_profile (profile info). No exclusions or when-not-to-use guidance are provided.

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