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. It explains the fallback behavior for postcode-only inputs (returns area-level data without a subject property), the requirement for address+postcode, and the scope of returned data. However, it does not mention potential limitations like data source freshness, cost, or whether the call can be slow or rate-limited.

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 three sentences, front-loaded with the core purpose, followed by a concise list of return data and then usage requirements/alternatives. Every sentence earns its place, with no filler or redundancy.

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 tool's complexity (six parameters, multiple data sources, output schema present), the description is complete: it names the required input, the return components, the fallback behavior, and the relevant sibling tools. The presence of an output schema means return-value details need not be duplicated, and the description already covers them at a high level.

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 100%, so the schema already explains all six parameters. The description adds meaningful semantic nuance for the address parameter by distinguishing between a full street address with postcode versus postcode-only, and clarifies the behavioral consequence of that distinction. This goes beyond simple restatement of 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 a specific purpose: 'Full data pull for a UK property in one call,' and enumerates the exact data returned (sale history, area comps, EPC, rental market, etc.). It distinguishes itself from siblings by emphasizing the 'one call' scope and explicitly naming property_comps/property_yield as alternatives for postcode-only queries.

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 explicit when-to-use guidance ('Full data pull for a UK property') and provides an exclusion: 'Postcode-only ... use property_comps or property_yield for postcode-only queries.' It also clearly states the required input format ('street address + postcode'), which is essential for correct invocation.

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