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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds a genuinely non-obvious behavioral trait — returned dates are plain calendar dates with no timezone conversion — which an agent could not infer from the annotations or schema.

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 the operation and scope, then a useful date caveat. The repeated 'Args:' block duplicates the schema almost exactly, which is mild waste, but the description is short overall.

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?

With an output schema present, return-value explanation is unnecessary, and the single optional parameter is fully specified. Minor gaps remain around what 'today' means (timezone/boundary) and behavior when no workouts are scheduled.

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 100% and the only parameter is fully documented there. The description restates days_ahead verbatim without adding format, edge-case, or boundary meaning beyond the schema, which is the baseline 3 case.

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 gives a specific verb and resource: retrieve upcoming scheduled workouts. It is clearly distinguishable from mutation siblings like create_workout/update_workout, though it never explicitly contrasts with the other read tools (get_workout_detail, get_programs) that could also return workout information.

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 phrase 'starting with today' and the days_ahead window imply the intended use case, but there is no explicit when-to-use/when-not-to-use guidance and no named alternative for related queries such as fetching a single workout.

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