download_workout

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

With no annotations, the description carries the full burden of behavioral disclosure. It does disclose that binary data cannot be returned through MCP and that the tool only confirms availability, but it leaves major ambiguities: does it write a file to a directory? Does it require set_fit_download_dir first? What side effects occur?

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 compact and front-loaded, with a useful caveat about binary data and an Args section. There is minor redundancy between 'Download a workout as a FIT file' and 'Downloads the workout in FIT format,' but overall it is efficient.

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?

For a side-effecting download tool with no annotations, important context is missing: where the FIT file goes, whether a download directory must be configured, and what 'confirms the workout is available' actually means for the caller. The output schema may explain the return value, but the tool's external behavior remains underspecified.

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 description coverage is 0%, so the description must compensate. It provides a minimal 'ID of the workout to download' for workout_id, which adds some meaning beyond the schema's property name and title, but it does not explain where the ID comes from or what constraints apply.

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 states a specific action ('Download'), a resource ('a workout'), and the format ('FIT file'). It is clear enough to distinguish from workout retrieval, though it does not explicitly differentiate itself from the similar sibling download_activity_file.

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?

There is no guidance on when to use this tool versus alternatives like get_workout_by_id, download_activity_file, or get_activity_fit_data. No prerequisites, exclusions, or related-tool routing are mentioned.

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