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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without help from the description. The description adds the useful fact that the returned set is a fixed, closed list of three named sources, but says nothing about permissions, response format, or pagination.

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?

A single sentence with the resource and its enumerated values front-loaded. Nothing is wasted and nothing is buried.

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 simple read-only enumeration tool with no output schema, the description is just barely sufficient: it names the sources but does not describe the shape of a returned entry (names, URLs, descriptions?) or what the optional query object can filter on. Adequate, with clear gaps.

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?

There is a single optional 'query' object parameter with schema description coverage reported at 100%, so the schema technically documents the parameter even though its own text ('Optional query parameters.') is generic and gives no filter syntax. Per the high-coverage baseline, 3 is appropriate when the schema carries the load.

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 sources used by Road Legal Pass') and enumerates the concrete sources (DVLA records, askMID, MIB), so an agent immediately knows what this returns. It does not explicitly contrast itself with siblings like road_legal_check or road_legal_catalogue, but the purpose is unambiguous.

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 when-to-use or when-not-to-use guidance and no mention of alternatives such as road_legal_check or road_legal_catalogue. The usage is only inferable from the name and purpose statement.

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