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

Annotations already establish read-only/idempotent/non-destructive/open-world false, and the description adds critical behavior: three-valued verdict semantics, source tracking distinction between true/checked_false vs defaulted_false/not_checked, credit cost, and UK-only scope. This is strong disclosure beyond 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 core purpose and the UPRN prerequisite are front-loaded, and the long category list earns its place by defining report scope. It is dense and could be more scannable, but has little 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?

Output schema exists so return structure needn't be explained, and the description covers scope, semantics, cost, UK restriction, and input acquisition. It is complete enough for an agent to decide and invoke correctly.

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?

With only one required parameter and zero schema description coverage, the description compensates by explaining that it is keyed on a UPRN rather than an address and giving the exact free workflow to obtain one. This adds substantial meaning beyond the bare integer 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 states a specific report over a property and enumerates the exact risk domains (flood, coal, heritage, environmental, planning, infrastructure). It is distinguishable from generic property_report/property_summary by its 'every designation and hazard flag' scope, though it does not explicitly contrast those siblings.

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?

Gives clear preconditions: UK only, costs 5 credits, keyed on UPRN not address, and directs to address_autocomplete then address_resolve. It does not explicitly say when to prefer property_risk_report over property_flood_risk or planning_designations, so not full 5.

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