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

With readOnlyHint=true, the safety profile is already covered. The description adds meaningful behavioral context by disclosing that the tool aggregates multiple data sources (ratings, recalls, complaints) into a single combined response. This is more informative than a simple read operation and helps set expectations for the returned payload.

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?

Two crisp sentences accomplish the goal with no filler. The first sentence scopes the purpose and contents, and the second gives immediate usage direction. Every word adds value.

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 read-only aggregating tool with a rich output schema and three fully described parameters, the description is sufficient. The agent knows what data to expect, when to use it, and that the result is a single response. No important operational detail is missing for the typical calling scenario.

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?

The input schema has 100% description coverage for all three parameters (make, model, modelYear), so the schema already carries the parameter meaning. The tool description does not add extra detail about how these parameters are used together; it only generically refers to 'a vehicle', so the schema remains the primary source of parameter semantics.

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?

The description states a specific verb ('Get') and clearly defines the resource as a comprehensive safety profile combining NCAP crash ratings, recalls, and complaint summaries. This distinguishes it from sibling tools that cover only one of these areas, so an agent can immediately identify how it differs.

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?

The description explicitly says to use this tool as the default when asked about vehicle safety, reliability, or purchase decisions, which is strong guidance. However, it doesn't explicitly name alternatives or state when NOT to use it, such as when a user specifically wants only recalls or only crash ratings without the combined context.

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