get_power_duration_curve

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

With no annotations, the description carries the full burden. It transparently reveals that it downloads multiple FIT files and may take 30-60 seconds. It also mentions it computes and returns season bests. However, it does not explicitly state it is a read-only operation or discuss any side effects beyond downloads, lacking full transparency.

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 slightly verbose with repeated mentions of downloading and durations, but it is well-structured and front-loaded with the core purpose. It earns a 4 because the extra details like the FTP formula and warning are valuable, though some redundancy exists.

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 provides a comprehensive context: it explains the output ('Returns season bests with which activity and date each best came from'), includes the standard durations, and gives a practical usage tip for FTP estimation. It is complete for the tool's complexity.

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 description adds meaning to both parameters beyond the schema: 'num_activities' is explained as number of recent activities with a max of 50, and 'activity_type' is explained as a filter with default 'cycling'. This fully covers the parameter semantics.

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 'Get season-best Power Duration Curve across recent activities' with a specific verb and resource. It distinguishes itself from sibling tools like get_cycling_ftp and get_lactate_threshold by focusing on the power duration curve derived from multiple 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?

It explains when to use the tool, especially for estimating FTP via the 20-minute best × 0.95 formula, and includes a warning about download time. However, it does not explicitly mention alternatives or when not to use it, though the FTP estimation context is clear.

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