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

Goes well beyond the readOnly/openWorld annotations: it discloses the data source (copart.com public search via a rendering residential proxy), the yield ceiling (20–50 lots per search), the account requirement for purchasing, and precise pricing semantics ($0.02 USDC per successful call via x402 on Base/Solana/Arc, failed calls free). These are exactly the operational facts an agent needs before spending money on a call.

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?

Front-loaded with what the tool is and does; two sentences, no filler. The long enumerated field list is partly redundant given an output schema exists, but it reads as one scannable clause rather than padding.

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?

Because an output schema exists, the description does not need to explain return values, and it still covers provenance, cost model, result-per-search ceiling, and account requirements. Minor gaps remain around pagination/result-limit behavior and whether queries accept lot numbers or URLs.

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?

Only one parameter with 100% schema coverage, so the schema already carries the burden and baseline 3 applies. The description's '(make, model, year...)' framing loosely reinforces query semantics but adds no syntax, limits, or matching behavior beyond the schema examples.

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?

Names a specific verb+resource (search of Copart US salvage/used vehicle auctions) and enumerates the returned data fields, so the agent knows exactly what it gets back. It does not explicitly differentiate from nearby siblings like social_carsandbids or social_carparts_com, leaving the agent to infer that this one is Copart-specific.

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 by the query examples (make, model, year) and the note that buying requires a Copart account, but there is no explicit statement of when to pick this over the sibling auction/inventory tools. No exclusions or alternative routing are given.

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