UK Property Data

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

No annotations are provided, so the description carries the full burden. It discloses key behavioral traits: the tool returns different data based on whether an address is provided (single property vs. aggregated area data), including details like energy rating, score, floor area, and property type breakdown. However, it doesn't mention potential limitations like rate limits, error handling, or data freshness, leaving some gaps for a tool with no annotations.

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 appropriately sized and front-loaded: it starts with the core purpose, then details the two usage modes in clear, bullet-like sentences. Every sentence earns its place by providing essential information without redundancy, making it easy to scan and understand quickly.

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 moderate complexity (two parameters, no output schema, no annotations), the description is largely complete. It covers purpose, usage guidelines, and parameter semantics effectively. However, without annotations or an output schema, it could benefit from more details on return formats or error cases, but it's sufficient for basic operation.

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?

The input schema has 100% description coverage, so the baseline is 3. The description adds significant value by explaining the semantic impact of parameters: it clarifies that 'postcode' is required for both modes, and 'address' determines whether the tool returns a single property match or aggregated area data. This goes beyond the schema's technical descriptions, enhancing understanding of how parameters affect output.

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: retrieving EPC certificate data for UK properties or postcode areas. It specifies the verb 'returns' and the resource 'EPC certificate data', distinguishing it from siblings like property_report or property_comps by focusing on energy performance data rather than general property information or comparisons.

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 explicitly states when to use this tool: 'With address: returns the matched certificate for that property' and 'Without address: returns all certificates at the postcode with area-level aggregation.' It also provides guidance on alternatives: 'Use this for area analysis rather than a single-property lookup,' though it doesn't name specific sibling tools, it clearly differentiates the two modes of operation.

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