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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, openWorldHint), so the bar is lower, and the description still adds genuine context: the tool is free, and the data provenance (CBS, Politie, Leefbaarometer) tells the agent the scope and trust level of the results. It omits any rate-limit, coverage, or freshness caveats, which keeps it out of 5 territory.

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 free/scope qualifier is front-loaded, followed by one dense sentence listing the payload and a short source line. Nothing is redundant, though the field enumeration is long enough to read as a spec dump rather than prose.

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?

With no output schema, the description does the heavy lifting by enumerating the returned metrics, and annotations carry the safety profile. It stops short of describing response shape, units, or behavior for an unresolvable postcode, but for a read-only lookup it is essentially complete.

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% and both parameters are documented in the schema with examples, so the baseline of 3 applies. The description only mentions 'for a postcode' and does not acknowledge the alternative CBS neighbourhood code input, so it adds no meaning beyond the 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 concrete resource (Dutch neighbourhood headline facts keyed by postcode) and enumerates the exact data returned — residents, WOZ value, sale price, owner-occupied share, liveability percentile, crime rate, distances. It never names the closely related sibling nl_neighbourhood or explains how this 'summary' differs from it, so an agent cannot fully disambiguate without opening both schemas.

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 leading 'Free.' hints at a free-vs-paid tier distinction and 'for a postcode' implies the lookup context, but there is no explicit when-to-use, when-not-to-use, or named alternative. Given the sibling nl_neighbourhood exists and is presumably the paid/detailed counterpart, the absence of routing guidance is a real gap.

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