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

With readOnlyHint/openWorldHint already covering safety, the description adds real context: the underlying GraphQL call, that Garmin chooses the window (~18 workouts over several weeks), and that an unenrolled user gets `[]`. It stops short of rate limits or pagination, but discloses return shape and the empty-state edge case.

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?

Front-loaded with purpose, then behavior, then edge case — efficient ordering with no filler. The GraphQL signature and DTO field dump are heavier than most agents need, keeping it just short of ideal brevity.

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 the description compensates by enumerating the returned entry keys (trainingPlanId, planName, classification, detailsDTO, workoutScheduleSummaries) and the empty case. For a 2-parameter nested-schema read tool this is nearly sufficient; only the `lang` value space is left undefined.

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 coverage is 50% (only calendarDate is described). The description compensates by naming all three GraphQL arguments and asserting lang and firstDayOfWeek are REQUIRED by Garmin, which tells the agent to populate the otherwise-undocumented nested `options` object. It still omits valid `lang` values, so it doesn't fully close the gap.

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?

States a specific verb+resource with scope: 'Enrolled training plans' workouts around a date, grouped by plan.' The 'enrolled' + 'grouped by plan' qualifiers separate it from sibling readers such as get_scheduled_workouts, get_adaptive_workout, and get_training_plans without needing to open any schema.

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 never says when to choose this over the many adjacent tools (get_scheduled_workouts, get_training_plan_by_id, get_next_scheduled_workout). The only usage signal is implicit: it covers enrolled-plan workouts. No exclusions, prerequisites, or alternative-routing guidance are given.

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