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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, not open-world), so the description's value-add is the ranking behavior and the name-matching limitation, both of which materially affect how results should be interpreted. It stops short of discussing empty-result or pagination behavior.

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 tight sentences, front-loaded with what the tool does and the accepted keys, then ranking and matching caveats, then filters. No filler and no repetition of annotation-covered facts.

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 search tool with an output schema, the description supplies the matching semantics, ranking and filter surface an agent needs to invoke it correctly. Minor gaps remain around empty-result and pagination behavior, but the output schema covers the return shape.

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 67%, and the description compensates by enumerating the filter axes (traffic area, vehicle category, status, licence type, presence in the latest DVSA file) and giving a licence-number example format. It adds interpretation (e.g. names match organisations only) beyond the raw field descriptions, though it doesn't document each filter value's syntax in prose.

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 (find) and resource (GB goods vehicle and PSV operators), plus every accepted search key. It reads distinctly from lookup siblings like get_licence or get_company, which require an identifier rather than performing a search.

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 the matching model and its limits (exact licence/company numbers rank first; names match companies and organisations only, so sole traders are only found by exact licence number), which tells the agent when this search will and won't succeed. It does not, however, name a sibling alternative (e.g. get_licence for full detail on a known number).

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