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

Annotations already cover safety (readOnly, idempotent, non-destructive, openWorld), but the description adds substantial extra context: the returned fields, that prices reflect delivery to the given country, that eBay results arrive as a separate ebay_results list sourced from the official API, and an affiliate-link/commission disclosure. It stops short of describing pagination or result-count behavior.

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 dense paragraph with essentially no wasted clauses — each sentence covers a distinct fact (multilingual query, AliExpress results, eBay results, affiliate disclosure). It is a little long and could be split for front-loading, but nothing is filler.

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 no output schema, the description carries the return-shape burden and does so well by listing listing fields for both sources. The main gap is the absence of any note on empty-result or fallback behavior when eBay has no matches.

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 every parameter is already documented. The description only reinforces the language/country/price-for-delivery semantics, adding no syntax or format detail beyond the schema, so the baseline of 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?

It names a specific verb (search) and resource (products) plus the concrete sources (AliExpress, and conditionally eBay) and the notable capability of natural-language queries in any language. An agent knows exactly what this does without opening the schema.

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?

Usage context is implied via 'shopper's own words in any language' and 'no need to know the English product name', and it explains the condition under which eBay results appear. There is no explicit when-not-to-use guidance or named alternative, though none exists among siblings.

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