UK Property Data

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

With no annotations provided, the description carries the full burden of behavioral disclosure. While it mentions the data sources and output ('gross yield figure'), it doesn't disclose important behavioral traits like whether this is a read-only operation, potential rate limits, data freshness, error conditions, or what format the yield figure takes. The description provides basic operational context but lacks comprehensive behavioral transparency.

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 perfectly concise with just two sentences that each earn their place. The first sentence establishes the core purpose, and the second explains the methodology and output. No wasted words, and the information is front-loaded with the primary function stated immediately.

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 calculation tool with 5 parameters, 100% schema coverage, but no annotations and no output schema, the description is adequate but has clear gaps. It explains what the tool does and its data sources, but doesn't describe the return format, error handling, or limitations. Given the complexity of combining two data sources for financial calculations, more context about reliability, data freshness, or calculation methodology would be helpful.

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%, so the schema already documents all 5 parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema - it mentions postcode and yield calculation generally but provides no additional syntax, format, or usage details for the parameters. This meets the baseline expectation when schema coverage is complete.

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's purpose with specific verbs ('calculate', 'combines') and resources ('rental yield', 'UK postcode', 'Land Registry sales data', 'Rightmove rental listings'). It distinguishes itself from siblings like property_comps, property_epc, and rental_analysis by focusing specifically on yield calculation rather than comparisons, energy certificates, or general rental analysis.

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 context by mentioning the data sources and purpose, but doesn't explicitly state when to use this tool versus alternatives like property_comps or rental_analysis. No specific exclusions or prerequisites are mentioned, leaving the agent to infer appropriate usage scenarios based on the yield calculation focus.

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