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

Annotations already carry the safety profile (readOnly, idempotent, non-destructive), and the description adds real value on top: data freshness ('results may be up to a minute old'), extra return fields for cross-listed cars (crossListed, marketPrice, marketCurrency), and the per-market currency rule for price filters. It leaves pagination/default-limit behavior and result ordering unexplained.

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 core purpose is stated first, filters second, edge-case return behavior third, and freshness last — a sensible front-loaded order with no filler. The parenthetical field lists make it slightly dense but each clause carries information.

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 an 11-parameter, zero-required search tool with no output schema and sparse schema descriptions, the definition covers nearly every filter, the currency semantics, and partial return-shape disclosure. Missing pieces are default limit, ordering, and whether all filters combine with AND.

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 coverage is only 27%, so the description does the heavy lifting: it enumerates free text, make, model, country, price range, maxKm, minYear, and fuel, and clarifies that price filters are interpreted in the searched market's currency (PLN in PL, EUR elsewhere). Only 'limit' is left without any narrative meaning.

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 active private-seller car listings on AutoPrivado') plus the scope restriction (active only, private sellers). This clearly separates it from get_listing (single fetch) and create_listing (mutation) among the siblings.

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?

Explains what each filter dimension does and, importantly, the condition under which cross-listed cars appear ('a country search also returns cars cross-listed into that market'). It never explicitly says when not to use it or names an alternative sibling, so it stops short of a 5.

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