get_activity_split_summaries

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 not state whether the operation is read-only, what data it returns in terms of format or pagination, or any authentication/rate-limit considerations. The only behavioral hint is the verb 'get', which implies a read but is not explicit.

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 plus an Args section, with no redundancy. It is front-loaded with the core purpose and immediately provides the parameter meaning. Very 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 simple one-parameter tool with an output schema, the description is minimally sufficient to understand what it does. However, given the large number of sibling tools that retrieve activity data, more context on when this specific split summary is appropriate (e.g., versus get_activity_typed_splits) would improve completeness. The output schema covers return details, so that is not a gap.

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 provides only the type and name for activity_id (coverage 0%). The description adds 'Garmin activity ID', which gives context on the expected format and domain. This is a modest improvement, but it does not elaborate on required format or how to obtain the ID.

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 tool returns per-split summaries of an activity with specific metrics (pace, HR, power). It specifies the resource (activity splits) and the action (get summaries). While it doesn't explicitly contrast with similar tools like get_activity_typed_splits, the mention of 'laps, intervals, rest' gives enough specificity to understand its scope.

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 such as get_activity_details or get_activity_timeseries. The description provides no context for selection, no exclusions, and no prerequisites. An agent would have to infer usage from the tool name alone.

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