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

Annotations already declare readOnlyHint=true, so the agent knows this is a safe read operation. The description adds value by listing the specific stats returned (avg price, median, price/m²) and the scoping behavior. No contradictions with annotations.

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 extremely concise: two sentences with zero wasted words. The first sentence immediately states the key output fields, and the second provides a clear usage hint. It is front-loaded and efficient.

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?

Given that there is no output schema and five parameters, the description provides only basic information. It lists three output fields but does not specify units, currency, or whether these are per-month for rent. It also does not explain the effect of listing_type or property_type. While it covers the core functionality, it leaves gaps for an AI agent to infer.

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?

Schema description coverage is only 20% (only 'neighborhood' has a description). The description adds meaning to 'neighborhood' by mentioning zone-level scoping but leaves four other parameters (city, country, listing_type, property_type) without any additional context. Enums for listing_type and property_type exist in schema, but the description does not clarify their effect on the output.

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 states the tool provides market statistics: average price, median, and price per square meter. It also mentions scoping with neighborhood for zone-level numbers. This distinguishes it from sibling tools like 'get_listing' or 'search_listings' which return individual property data.

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 implies usage by saying 'Scope with neighborhood for zone-level numbers,' hinting when to use the neighborhood parameter. However, it lacks explicit guidance on when to use this tool versus alternatives like 'search_listings' or 'rental_yield.' No exclusions or prerequisites are mentioned.

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