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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so safety is covered. The description adds genuinely useful behavior beyond that: only currently buyable/biddable listings appear, sold/reserved/expired are excluded, each item carries a whoppah.com link, and payment occurs off-tool on whoppah.com.

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 single paragraph is dense and front-loaded: catalogue identity first, then usage trigger, then filter mechanics, then availability/freshness, then the buyer-facing link. No sentence 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 an output schema present, return shape need not be explained, and annotations cover the safety profile. The description supplies everything else an agent needs to call this correctly: usage trigger, filter strategy, freshness guarantee, and the critical post-call instruction to hand the buyer the whoppah.com link.

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 0% across 13 parameters, so the description must carry the load, and it names most filter dimensions (category, brand, designer, price range in EUR, condition, colour, material, seller country) plus the free-text query concept. It leaves page, sort and limit undocumented, including valid sort values or pagination behavior, so it is strong but not complete.

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 Whoppah's live catalogue') and scopes the domain concretely (furniture, lighting, art, decor, designer bags). It is distinguishable from siblings like get_item and similar_items without opening any 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?

'Use it whenever someone wants to find, compare or buy a design piece' gives a clear trigger condition and the description explains how to combine free-text with filters plus facet counts. It does not, however, name alternatives or exclusions (e.g. when to prefer get_item, list_categories or list_brands_designers for browsing facets).

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