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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds the cost per call (60¢) and clarifies the output is a top comparable set, which is useful but does not disclose return format, pagination, or any limitations beyond what annotations imply.

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 brief and front-loaded with the core purpose, followed by a useful pricing note. No unnecessary words are present, though the extreme brevity leaves out important operational context.

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 one-parameter tool with no output schema, the description should at least clarify what data is returned and what gnaf_id refers to. It only states 'top comparable sales' and a price, leaving an agent to guess about response structure, parameter semantics, and how this compares to related tools.

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 0%, and the description does not explain gnaf_id or how it relates to the subject property. The phrase 'subject property's value' weakly implies gnaf_id identifies that property, but the description does not compensate for the lack of parameter documentation.

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 the tool returns top comparable sales used to triangulate the subject property's value, which identifies both the resource (comparable sales) and the purpose (valuation triangulation). It is clear enough to distinguish from sibling tools like properties_comparables_all by 'top comparable sales', though it does not explicitly name alternatives.

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?

There is no guidance on when to use this tool versus sibling tools such as properties_comparables_all, properties_comparables_cma_single_comp, or properties_comparables_recent_sales_nearby. The phrase 'used to triangulate... value' implies a use case, but no explicit context, exclusions, or alternative routing is provided.

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