Find discounted eBay listings

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds behavioral details: it filters by advertised savings threshold and sorts by landed price, which goes beyond the annotations. It does not describe pagination or response format, but with the annotations covering the basic side effects, this is adequate.

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 consists of two concise sentences: the first states the primary action, the second adds the filtering and ordering behavior. There is zero fluff, and every word earns its place.

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?

Given 5 parameters, no output schema, and helpful annotations, the description is sufficiently complete. It explains the core filtering and ordering behavior, which is the key differentiator. While it doesn't describe return fields or pagination, the simplicity of the tool and schema richness compensate. It could add more detail on the response structure, but it is not critically missing.

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 has 100% description coverage for all 5 parameters, each with its own description. The tool description does not add additional parameter-level clarification beyond what the schema provides, so the baseline of 3 is appropriate per the rubric.

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 verb 'Search' and the resource 'eBay listings' with a specific scope: discounted items meeting a savings threshold. It distinguishes itself from siblings like search_ebay by focusing on advertised discounts and cheapest landed price first, making its purpose unique.

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 when to use it (when seeking discounted items) via its focus on savings thresholds and ordering, but it does not explicitly mention alternatives or exclusions. The existence of sibling tools like search_ebay suggests a differentiation, but no direct comparison is made, so it's clear context without explicit when-not guidance.

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