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

Annotations already mark the tool as readOnly and non-destructive, and the description adds useful behavioral detail beyond that: it returns the lowest price per day over 30 days, is limited to one product, and warns that available markets may change over time. This gives the agent expectations about scope and dynamic data.

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 well structured, front-loading the core purpose before usage guidance and parameter details. The argument list is slightly redundant with the schema, but the added semantic value justifies the length.

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?

The tool is simple with only two parameters, annotations already establish the safety profile, and an output schema exists to describe return values. The description covers purpose, usage triggers, parameter semantics, and the dynamic-market caveat, leaving no critical gap.

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?

With 0% schema description coverage, the description fully compensates by defining both parameters. product_slug is explicitly tied to the output of search_beauty_prices, and country is explained with concrete market codes and a pointer to get_service_info for the authoritative list.

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 a specific verb and resource: 'Return the recent price history for one product,' and narrows it further with 'lowest price per day over the last 30 days.' It clearly differentiates this from siblings like compare_product_prices by emphasizing single-product history over time.

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 explicitly states when to use the tool: when the user asks whether a price changed recently, whether a discount is new, or whether today's price is typical. It also tells the agent to get product_slug from search_beauty_prices, though it does not explicitly state when not to use it or name alternative tools for comparison.

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