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

Annotations already declare readOnlyHint=true and openWorldHint=false, covering the safety profile, so the bar is lower. The description adds genuinely useful context beyond that: a 12-month weighted calculation window and the three computed metrics. It does not explain edge cases like sparse rental data or how the gross rental yield is derived, making it adequate but not rich.

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 28-word sentence that front-loads the action ('Compare buying vs renting'), immediately lists the metrics, and closes with the optional filter. Every clause earns its place with zero filler or repetition of the title.

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?

With no output schema present, the description carries the burden of describing return values, and it does so by enumerating the three metrics an agent will receive. For a read-only, two-parameter tool this is nearly complete; the only gaps are minor presentation details such as currency, units, and yield formatting.

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 100%: slug is documented as the location slug returned by search_locations, and propertyClass carries a full enum. The description's 'one community or area' echoes slug's semantics and 'Optionally filter to one property class' reaffirms the schema's optionality, adding modest confirmation but no new meaning beyond what the schema already provides.

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 opens with a specific verb and resource, 'Compare buying vs renting in one community or area,' and enumerates the exact metrics computed: 12-month weighted median sale price, median annual rent, and implied gross rental yield. Among the siblings (get_market_overview, get_price_history, rank_communities, etc.), this is the only tool producing a buy-vs-rent comparison with rental yield, so it is clearly distinguishable.

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: it is scoped to one community or area and optionally filterable to one property class, so an agent knows this is the tool for a localized buy-vs-rent analysis. It stops short of a 5 because it never names alternatives or states when-not-to-use conditions, such as when a broader market overview or price-history trend is the better fit.

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