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

Annotations already establish that this is a read-only, idempotent, non-destructive, closed-world check. The description adds useful domain behavior: it enumerates the three legal checks and states that it does not judge whether the rent is fair, clarifying the tool's limits beyond the safety 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 dense but front-loaded: it leads with the check being performed, then the legal tests, the jurisdictional scope, and the fairness limitation. Every clause contributes useful selection or invocation context.

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 output schema, complete parameter descriptions, and clear annotations, the description supplies enough context for correct selection and invocation. It covers scope, legal checks, and the key limitation that fairness is not assessed.

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 five parameters thoroughly. The description adds meaningful context by tying those inputs to the substantive legal tests, such as the two-month timing rule and the one-year rule based on prior increase history.

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 verb and resource: checking a landlord's rent-increase notice for a Welsh periodic standard occupation contract. It also names the exact legal checks and the jurisdiction, which distinguishes it from the generic and other UK-jurisdiction rent-increase 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?

It clearly limits use to Wales and explicitly excludes fairness of rent from the tool's scope, which gives strong when-to-use and when-not-to-use context. It does not explicitly name sibling alternatives such as check_rent_increase_notice or the Scotland/Northern Ireland variants.

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