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

No annotations are provided, so the description must disclose behavior. It states the data is current weekly retail sales rank and 4-week momentum, which is useful context. However, it does not mention error behavior for invalid disc_id, whether the operation is read-only, or how 'momentum status' is defined. The description only partially carries the transparency burden.

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?

The description is a single, front-loaded sentence with no filler. Every phrase adds information: specific resource, regions, time frame, and momentum 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 one-parameter read tool with no output schema, the description states what is returned (rank per region and momentum status) and names the regions. It omits response shape and error handling, but these are minor for such a simple 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?

The input schema already fully describes disc_id with examples and formats, and schema coverage is 100%. The tool description adds no parameter-level details beyond the schema, so the baseline 3 applies.

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 opens with the verb 'Retrieve' and specifies the exact resource: a single disc's weekly retail sales rank across named regions (Global, Europe, Americas, Oceania, Asia) and its 4-week market momentum status. This clearly differentiates it from siblings like get_weekly_rankings (list-oriented) and get_market_movers (market movers).

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 implies the tool is for a single disc's ranking/momentum but never explicitly states when to choose it over siblings like compare_discs, find_similar_discs, get_disc, get_market_movers, or get_weekly_rankings. No exclusions or alternatives are mentioned, so usage guidance relies on inference.

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