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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds only that results are category-scoped and exclude collectibles; it says nothing about how prices are aggregated or what happens with sparse data, and the redundant 'typical price vs typical price' adds no behavioral information.

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?

It is a single front-loaded sentence with no filler beyond what is needed, but the clause 'typical price vs typical price' is literally redundant and consumes space that could have clarified the savings output or the limit parameter.

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 two-parameter read tool with no output schema, the definition covers the core comparison and the category dependency. It still leaves the limit parameter and the shape of the returned savings data unaddressed, so an agent knows what it asks for but not fully how to tune or read the result.

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 parameter meaning. It does clarify that the category parameter is a key obtained from list_categories and must not be a collectible, which is genuinely useful. However, the limit parameter is entirely unexplained, leaving half the inputs undocumented.

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 states a specific comparison (used/refurbished price vs new price, expressed as savings) over a category, which is a distinct purpose from siblings like get_price or price_moves. The phrasing 'typical price vs typical price' is awkward and blurs the exact output, but the core verb+resource is identifiable.

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?

It gives one concrete usage constraint: the category must be a key from list_categories, and collectibles are excluded. It does not say when to prefer this over deals or get_price, nor what to do if a category is a collectible, so guidance is implied rather than explicit.

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