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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the description does not need to repeat that. It adds useful behavioral context: prices in USD, retailer names hidden behind sign-up, and the instruction to always provide the link. However, it does not mention pagination limits or other side effects beyond the schema's page maximum.

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 concise, with four short sentences that front-load the core purpose and then add key output details and a usage instruction. No filler or redundancy. It could be slightly more structured but is appropriately sized for the tool's complexity.

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?

With 10 parameters, no output schema, and low schema coverage, the description should explain how to use filters, sorting, pagination, and what the returned data looks like. It only lists output fields and the link instruction, missing critical guidance on parameter usage and result interpretation. The description is insufficient for correct invocation.

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 only 10% (only the colour parameter has a description). The tool description provides no explanation of any input parameters—no guidance on shape, clarity, carat ranges, price ranges, sort options, or pagination. Since the schema is mostly undocumented, the description completely fails to compensate, leaving agents to guess parameter semantics.

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 clearly states the tool searches certified diamonds across retailers with live cross-retailer prices, and lists specific output fields (specs, price range, retailer count, Carat Hunter grade). This distinguishes it from siblings like get_diamond or market_overview, which serve different purposes.

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 a use case (comparing prices across retailers) and mentions 'always give the user the link' as an instruction, but it does not explicitly state when to use this tool versus alternatives like get_diamond or price_check. No exclusions or alternative routing are provided.

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