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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false), so the description is not burdened with that. It still adds real behavioral context beyond annotations: default filtering to agent-purchasable products, the fact that include_unsellable surfaces unaudited/deprecated items that are flagged and not buyable, and the thin-result fallback fields (suggestions/did_you_mean/available_domains).

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?

A single dense paragraph that front-loads what the tool does before moving to query handling, return format, and the unsellable caveat. Every sentence carries information; it is on the long side but not padded, and the caveat is deliberately placed last.

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 9 parameters, no output schema, and no required fields, the description does the expected work: it explains the retrieval mode, the response shape, the low-match fallback, and the default-scope behavior. Pagination and price/verified filters are left entirely to the schema, which is acceptable but leaves a small gap for a 9-parameter tool.

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 67%, so the schema carries most of the load (tags, domain, category, verified_only, include_unsellable are all described there). The description adds value only for the query parameter (natural-language handling, stopword/phrase tolerance, synonym expansion) and reinforces the include_unsellable default; it says nothing about page, page_size, max_price_usd, or verified_only.

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?

States a specific verb and resource ('Search the Datanest catalogue of digital technical products') and specifies the query mode (natural-language intent) and the return shape (ranked product cards with canonical URLs). It is clearly distinguishable from get_product_details or compare_products by verb, but it never names a sibling or explicitly contrasts itself with the retrieve-by-id tools.

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 is implied rather than prescribed: the query examples hint at when this tool is appropriate, and the include_unsellable note implies a default scope. There is no explicit statement of when to prefer this over get_product_details/compare_products, no mention of what to do when a query is too specific (aside from the implicit did_you_mean fallback), and no exclusions.

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