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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds important behavioral context: the calculation is performed locally from published rates, the result is indicative and non-binding, and the final charge occurs elsewhere. This goes beyond the annotations without contradiction.

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?

The description is two sentences, front-loaded with the core action ('Approximate price'), and avoids redundancy. Every clause contributes value, including the caveat about non-binding status and the checkout reference.

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 4-parameter tool with an output schema, the description covers the essential purpose, the nature of the result (approximate, non-binding), and the follow-up action (checkout). It does not detail return values, but the output schema covers that, so the description is sufficiently complete.

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 schema description coverage is 50%, leaving insuranceLengthDays and travellerCount without semantic explanations beyond numeric constraints. The tool description does not elaborate on any parameters, so it adds no additional meaning. This falls at the baseline for a schema that partially covers parameters.

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 uses a specific verb ('Estimate') and a specific resource ('price for a war-risk travel policy'), and it distinguishes itself from siblings like get_insurance_facts by clarifying it is a local, non-binding calculation. The phrase 'not a partner quote' reinforces its distinct role.

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 clearly implies when to use the tool: for an indicative price estimate before checkout. It explicitly states that it is not a binding offer and that the exact amount is charged during checkout, providing context on its limitations. However, it does not explicitly name alternative tools or list specific situations to avoid, so it stops short of a 5.

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