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

Annotations already mark the tool read-only, idempotent, and non-destructive, and the description adds meaningful behavioral context beyond that. It explains the TrueRent service model, the free rental review process, and the critical output limitation that no rates, benchmarks, or estimates will be returned.

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 four sentences and front-loads the purpose and the main limitation ('It does not return rates, benchmarks, or estimates'). The TrueRent background information is relevant but slightly promotional; still, every sentence earns its place without padding.

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 informational tool with an output schema, the description tells an agent when to invoke it, what it will return, and what it will not do. It could be slightly stronger by explicitly naming the sibling action tool request_free_review for when the user is ready to start a review, but nothing essential is missing.

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, with both metro and situation already fully documented. The description does not add parameter-level meaning beyond what the schema provides, so the baseline 3 is appropriate.

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 clearly identifies this as an informational tool for construction equipment rental pricing, rates, invoices, fees, and quote comparisons. It states the exact deliverable (service description and how to start) and explicitly differentiates itself by saying it does not return rates, benchmarks, or estimates, which separates it from a tool that actually executes a review.

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 'Use this when a user asks about equipment rental pricing...' and sets a clear boundary by stating it does not return actual rates or estimates. It does not explicitly name request_free_review as the alternative for starting the review, but the description's 'how to start' phrasing implies the next step.

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