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

Annotations already cover readOnly, idempotent, openWorld and non-destructive, so the bar is lower, yet the description still adds real behaviour: unattributed councils return an explicit "not researched" answer rather than a guess, each result carries its source, and it disclaims legal advice. That is genuine context beyond the structured fields.

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?

Front-loaded with the usage trigger, then the return payload, then constraints and disclaimer. Four dense sentences with little waste, though "Read-only" restates the readOnlyHint annotation and could be dropped.

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?

There is no output schema, so the description carries the return-value burden and does so thoroughly: it enumerates licence need, licensing schemes, register window, flood zone, conservation area, per-item sources and councilPage. Combined with the England-only and no-guessing behaviour, an agent has everything needed to call it and interpret the result.

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% and both parameters are fully documented in the schema, including the household enum breakdown. The description only alludes to "household type" and adds no format or edge-case detail, so the baseline of 3 applies.

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?

States a specific verb and resource: it checks what rules apply to a rented home at an England postcode and returns licence need, schemes, register window, flood zone and conservation area. The scope is concrete, though it never names the sibling tools (council_licensing, get_rule, search_rules) that overlap with the licensing portion of its output.

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?

"Use when someone asks what applies to a rented home at a postcode in England" gives a clear triggering condition, and "England only" bounds it. It stops short of naming an alternative or stating when another tool would be better, so no explicit exclusions.

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