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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety profile is covered. The description adds genuinely new behavior beyond that: the exact cost model (0.01 USDC via x402 or 5 credits) and the upstream data sources (CBS, Politie, Leefbaarometer). It omits what happens when neither postcode nor code is supplied, which matters since both parameters are optional.

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 deliverable, then use cases, then sources and cost in a single tight paragraph. No filler sentences; every clause carries information an agent can act on.

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 correctly compensates by enumerating the returned fields, and it discloses the paid access model. The only real gap is the unresolved requirement of at least one of postcode/code, which is left implicit despite both params being optional.

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 both parameters are already documented, and the schema itself labels 'code' as an alternative. The phrase 'for any postcode or CBS neighbourhood code' reinforces the either/or relationship but adds no format or validation detail beyond the schema examples (2517AS, BU05182245). Baseline 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?

Specific verb+resource with a full content inventory: population/age mix, housing, income, energy, amenity distances, crime, liveability. An agent immediately knows what comes back. However, it never differentiates itself from the close sibling nl_neighbourhood_summary, leaving the boundary between 'profile' and 'summary' unclear.

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 names concrete usage scenarios (real estate, relocation, retail site selection, market research) and states the access cost, which is useful routing context. But it never states when NOT to use it or points to the obvious alternative (nl_neighbourhood_summary, nl_crime, nl_house_prices) for narrower needs, so selection among siblings is left to inference.

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