EU Second-Hand Marketplaces Scraper: Vinted, OLX & More

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

Annotations already declare readOnlyHint and openWorldHint, but the description adds real value beyond them: currency conversion into euros, a deal score, a per-country median, and explicit per-result pricing ($0.003 run start, $0.002 per listing). Auth/rate-limit specifics are absent, keeping it out of the top band.

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?

Two sentences, no filler, and the geographic scope plus output contents are front-loaded before the pricing note. The superlative claim ('the biggest') is mild marketing rather than wasted length.

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 usefully sketches what comes back (listings, euro prices, deal score, median price per country) and discloses the pay-per-result cost model. The main hole is sibling differentiation, which matters here given search_vinted and search_kleinanzeigen sit alongside it.

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 with useful detail (currency conversion targets, enum meaning, per-marketplace defaults). The description adds essentially nothing parameter-level beyond echoing euro conversion, 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?

States a specific verb and resource ('search... second-hand marketplace of up to 18 European countries') and names concrete marketplaces, so the agent knows this is a multi-country second-hand listing search. However, it never distinguishes itself from the direct siblings search_vinted and search_kleinanzeigen, which cover single marketplaces, so routing still needs inference.

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?

There is no explicit when-to-use or when-not guidance, and the obvious alternatives (search_vinted, search_kleinanzeigen for single-marketplace queries) are never mentioned. Some usage hints live in the schema ('Newest first is best for monitoring'), but the description itself gives none.

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