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

Annotations already declare this a safe, idempotent, read-only operation, lowering the bar. The description adds genuine behavioral context beyond them: default returns the most recent periods, while supplying `period` narrows to a single period. Return/pagination mechanics are not described, but that gap is minor given the annotation coverage.

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?

Three short sentences, front-loaded with what the tool returns and zero redundancy. Each sentence earns its place: contents, default-vs-explicit period behavior, and usage context.

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 annotated read tool with no output schema, the definition covers purpose, default scoping, and usage context adequately. It omits how `limit` caps or paginates results, a small but real gap for an agent deciding how to call it.

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 67% – scope and period carry their own descriptions, but `limit` (default 12, max 60) is undocumented in the schema and is never mentioned in the description either. The description's note about 'most recent periods by default' adds marginal meaning to `period`, so it neither compensates for the gap nor falls below the baseline.

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 and precisely what is returned: weekly/monthly medal winners ranked gold/silver/bronze. The clause 'see what actually won, not just what launched' distinguishes it from the launch-oriented siblings (search_launches, list_ship_week) without opening either 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 'use this to see what actually won, not just what launched' line gives clear context for when this tool is the right choice versus launch-listing tools. It stops short of naming an explicit alternative tool or stating when-not to use it, so it lands just below the top band.

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