Latest new-car price quotes

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds real context beyond that: each row carries the date of its last quote and a day-over-day percent change, and the result set is limited to recent quotes. It does not state sort order, whether results are truncated by the limit, or what happens when query matches nothing.

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?

Three short sentences, zero filler, with the core purpose front-loaded before the sibling comparison and the use cases. Every sentence carries distinct 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 a three-parameter read tool with no output schema, the description says enough: it names the returned fields (percent change, last-quote date), the breadth of coverage, and the intended follow-up tool. Missing only ordering and empty-result behavior, which are minor for this complexity.

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 year, limit and query are all documented with ranges, defaults and examples in the schema itself. The description adds no parameter-level detail beyond implying recency, which puts it at the baseline for a fully documented schema.

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 ('List the most recent price quotes of new cars') plus the payload detail ('with the day's percent change'). It also distinguishes itself from two named siblings, kn_price_list (broader variant coverage, including older models) and kn_price_history, so an agent can separate it without opening a 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?

Gives two concrete use cases ('see what moved lately' and 'find a variant's exact English name for kn_price_history') and explicitly routes comparison with kn_price_list. The gap is the sibling kn_price_movers, which appears to overlap with the 'what moved lately' case and is never mentioned or excluded.

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