Build a source-aware swim progress report

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

With no annotations present, the description carries the behavioral disclosure burden. It adds a useful boundary by stating it does not derive pace trends from moving time divided by distance. However, it does not clarify whether the operation is read-only, what output format to expect, how data completeness is determined, or what happens when no matching swim data exists.

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 sentences, no filler, and each sentence adds value: the first states the operation and scope, the second clarifies a non-behavior and the prerequisite. The most important information is front-loaded.

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?

There is no output schema and no annotations, so the description should explain what the report contains. It does not describe return values, date range handling, source-awareness details, or edge cases like missing Garmin data, making it incomplete for a 4-parameter reporting tool.

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 for missing parameter meaning. It maps athleteId, startDate, endDate, and poolLengthM to broad concepts ('requires athleteId', 'date range', 'optionally within one pool length'), but it does not explain ordering, defaults, optionality semantics, or the meaning/units of poolLengthM beyond the schema constraint.

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 verb and resource: 'Compare Garmin swimming summaries and data completeness over a date range, optionally within one pool length.' It distinguishes itself from siblings by naming what it does and explicitly stating what it does not do ('does not derive pace trends from moving time divided by distance').

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 provides a clear usage context (comparing swimming summaries and data completeness over a date range) and a prerequisite ('Requires athleteId from list_athletes'). However, it does not say when to prefer this tool over alternatives such as get_swim_laps or cycling_progress_report, nor does it give exclusion conditions.

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