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

With no annotations, the description carries the disclosure burden. It clearly states a pass/fail return and a follow-up to CIBSE TM59, plus the caveat 'Indicative,' which is useful behavioral context. It does not detail edge-case behavior, but it covers the core behavior sufficiently.

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, with the core purpose and scope front-loaded. Every clause adds relevant information: the regulation, the test criteria, the return type, and the indicative caveat. No redundant filler is present.

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 6-parameter check tool with no output schema and no annotations, the description is reasonably complete. It explains what the tool checks, what it returns, and what happens on failure. It does not explicitly list all parameters or prerequisites, but the schema covers required fields and enums, and the added caveat 'Indicative' sets user expectations.

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 only 33%, so the description must compensate. It explains that glazing area is based on orientation, risk zone, and cross vs. single aspect, which adds meaning to most_glazed_facade, location_risk, and cross_ventilation. It also mentions minimum free ventilation area, covering provided_free_area_m2. However, floor_area_m2 and glazing_area_m2 are not directly elaborated, leaving some reliance on naming conventions.

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 performs a UK Approved Document O 2021 simplified-method overheating check for new residential buildings, with specific tests for glazing area and ventilation. It distinguishes itself from sibling tools by referencing the exact regulatory framework and method.

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 no explicit guidance on when to use this tool instead of siblings. It mentions that it points to CIBSE TM59 modelling on failure, which implicitly indicates a fallback, but it does not state when an agent should select this tool over related tools like thermal_load or estimate_cooling_load.

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