list_activities

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

Annotations already declare readOnlyHint and idempotentHint, so no duplication needed. The description adds useful behavioral context beyond annotations: it returns compact metrics, omits GPS and owner details, and uses an inclusive date range. This adds value without contradiction.

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 front-load the purpose and add key details. No fluff, every word earns its place. The structure is clear and 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?

Given the availability of an output schema and rich annotations, the description is adequate for a list tool. It covers the core purpose, date inclusivity, and notable omissions. However, it could be more complete by mentioning pagination or limit behavior, and by explicitly contrasting with sibling detail tools.

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 explains the date range inclusivity and gives an example for activity_type, but does not mention the 'limit' parameter at all, and implicitly treats start_date/end_date as a pair without specifying which are required. Over half of the parameters remain unexplained.

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 it lists completed Garmin activities within an inclusive date range. It distinguishes itself from siblings like get_activity_summary or get_activity_splits by focusing on listing rather than details, and from list_workouts by specifying 'activities' instead of 'workouts'.

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 a high-level list of activities) but does not explicitly mention alternatives or when not to use this tool. Comments about omitting GPS and owner details hint at limitations but do not direct the user to sibling tools like get_activity_summary for richer data.

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