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

Annotations already declare readOnlyHint, idempotentHint and closed-world behavior, so safety is covered. The description adds that results are 'long-run' costs rather than a single quote, which is meaningful context, but says nothing about the role of the seed parameter, latency, or the shape of the response.

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 front-loaded sentence with no filler or repetition. It is efficient, though its brevity is arguably under-specification rather than true conciseness given the tool's 11-parameter surface.

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 an 11-parameter, no-output-schema, 0%-coverage calculator, one sentence is not enough: an agent cannot tell what inputs are mandatory, what 'current auto profile' resolves to, or what the comparison returns. The readOnly annotation covers safety only, leaving substantive 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?

With 11 parameters and 0% schema description coverage, the description must carry the parameter burden and it does not. It gestures at the two deductible parameters via 'collision and comprehensive coverage costs' but leaves state, zip, age, gender, seed, make, model, year and style entirely unexplained.

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 names a specific action (compare) and resource (collision and comprehensive coverage costs) scoped to the current auto profile, which separates it from the home and umbrella calculators in the sibling list. However, it never explicitly contrasts itself with auto_estimates, so the agent must infer the distinction.

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 phrase 'for the current auto profile' hints at a precondition but the description never states when to choose this tool over auto_estimates or other calculators, nor any exclusions. It is implied usage only, with no routing guidance.

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