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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuine behavioral context beyond that: the aggregation is a total across an inclusive from/to window, and the window defaults to the last 30 days when omitted. It does not mention pagination, limits, or empty-result behavior, but the annotated tool needs less of that.

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, zero filler. The usage trigger is front-loaded and the second sentence delivers scope, defaults, and return contents compactly.

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?

An output schema exists, so the enumerated return values are supplementary rather than load-bearing, and usage plus default window are covered. The remaining gap is the accepted date string format for from/to, which is undocumented in both schema and description, plus no guidance on zero-data ranges.

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 carry both parameters — and it does define their roles ('Totals from `from` to `to`') plus the default window. However, both are typed only as plain strings with no format guidance (ISO date? relative?), which is the critical missing detail for a date-range tool, so it compensates only partially.

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 (retrieve training stats overview over a period) and enumerates exactly what is produced: workouts, volume, weekly volume trend, muscle distribution, top 5 exercises. This distinguishes it from siblings like get_weekly_summary and get_workout_history without the agent needing to open a 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?

Opens with an explicit trigger condition ('Use this when the user asks for an overview of their training over a period, such as volume trends or muscle-group balance'), which is strong when-to-use guidance. It does not name or exclude the overlapping siblings (get_weekly_summary, get_workout_history), so routing between near-duplicates is left to inference.

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