polar_download_exercise

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

Annotations already indicate not read-only, not destructive, and idempotent; the description adds file-format behavior and the GPS constraint without contradicting the annotations.

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?

Two concise sentences that front-load the purpose and contain no redundant or irrelevant wording.

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?

Sufficient for a straightforward download operation with two clearly described parameters and no output schema; could optionally mention overwrite behavior or success indication, but these are not essential.

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 covers both parameters, and the description adds meaningful detail by explaining that file extension determines format and that GPX requires GPS data.

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?

Clearly states it downloads exercise data to a file in FIT, TCX, or GPX format, distinguishing it from sibling get/list tools by its file-download purpose.

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?

Implies when to use it—when a file export is needed—and notes the GPX GPS restriction, but it does not explicitly contrast with alternatives like polar_get_exercises.

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