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

Annotations already indicate readOnly and non-destructive behavior. The description adds valuable context by noting data is 'source-dated,' 'active,' and that rent-to-price is a 'derived asking-price ratio, not observed income, net yield, valuation, forecast, ranking, or recommendation.' This prevents misinterpretation beyond what annotations provide.

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 two sentences, front-loaded with the core function and followed by an essential caveat. Every word earns its place, with no redundancy or filler.

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 the output schema exists and annotations cover safety, the description sufficiently covers purpose, scope ('one district'), and important disclaimers. It could be slightly more explicit about sibling differentiation, but overall it is complete for a simple read-only tool with structured output.

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 50%, with district described as 'District name (2-60 chars)' and city as an enum. The description does not elaborate on parameter meaning beyond identifying 'one district,' but the city enum values are self-explanatory. It adds no additional semantics beyond the schema.

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 returns 'source-dated active sale/long-term-rent listing counts and asking-price aggregates for one district,' with a specific verb and resource. This distinguishes it from siblings like get_price_index or compare_cities by focusing on asking-price context at the district level.

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 use for a single district's aggregate asking-price data, but does not explicitly state when to use this versus alternatives such as compare_cities or get_yield_estimate. No exclusions or alternative guidance is provided, leaving usage to be inferred from the tool's purpose.

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