Get comparable rentals near a Redfin property

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety and variability. The description adds value by specifying the output content (similar active rentals with rent, distance, URL) and the source of inputs (upstream property data). This exceeds annotation coverage 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?

Two sentences with zero waste. The first sentence states the core function and output; the second covers use case and input provenance. Information is front-loaded and every clause earns its place.

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 read-only tool with robust annotations and no output schema, the description covers the essential aspects: what it returns, how it's useful, and where inputs come from. It doesn't mention pagination or distance limits, but these are not critical for a comparables tool and the description is otherwise sufficient.

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 coverage is only 40%, so the description must compensate. It does by naming the parameter groups: 'rent estimate range + lat/lng + propertyId', which maps directly to the five parameters. It also clarifies the rent estimate low/high as a range and notes they can be equal. However, it does not explain the meaning of property_id beyond 'from upstream', which is a minor gap.

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 a specific verb ('Find') and resource ('nearby rental comparables for a given property'), details the criteria (similar bed/bath/sqft) and outputs (monthly rent, distance, Redfin URL). It also conveys the use case (estimating rent, finding nearby rentals), which distinguishes it from siblings like redfin_get_property or redfin_search_properties.

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 gives clear context for when to use the tool: when you have a property and need rental comparables, and it specifies that inputs typically come from upstream redfin_get_property or the property page. It does not explicitly state exclusions or alternatives, but the context is sufficient for an agent to decide when to invoke it.

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