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

Annotations already declare readOnlyHint=true, openWorldHint=true, destructiveHint=false, so the safety profile is covered. The description adds only the multi-site scope, and says nothing about caching behavior (despite the noCache parameter), result caps, or pagination limits that a searcher would need.

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 second sentence is a ~25-phrase keyword dump that repeats 'eBay X' with no added information per clause. Only the final clause ('even if eBay is not explicitly mentioned') earns its place; the rest is padding that dilutes the front-loaded purpose statement.

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 15-parameter, annotation-covered read tool with no output schema, the description is minimally adequate. It omits any indication of what a result contains (titles, prices, seller, shipping) or how paging behaves, which an agent pricing out a search would benefit from.

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 100%, so all 15 parameters are already documented in the schema with examples and enumerated options. The description adds no parameter meaning beyond what the schema carries, 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 first sentence gives a specific verb and resource ('Search and browse product listings across multiple eBay international sites'), which is clear on its own. However, it never distinguishes itself from the near-identical sibling nexscope_data_ebay_search, leaving an agent unable to choose between them from the description alone.

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 long trigger list ('eBay product search, eBay listing query, eBay price comparison…') implies when to use it, which is real but redundant guidance. There are no exclusions and no named alternatives — nothing tells the agent when to prefer Amazon/Walmart/Temu search tools or the duplicate eBay tool.

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