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

Annotations already declare readOnly/openWorld/idempotent/non-destructive, so safety is covered; the description adds genuinely new behaviour: results are capped at six example rows plus a true match count and a link to the full file. It also discloses the radius default and cap via the schema, and the address-omission semantics. Minor gap: no indication of latency or how the 'link' is produced.

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 core capability, then a clean parameter rule, then concrete example invocations that each earn their place by showing the address-present and address-absent modes. The record-type enumeration is long but informative rather than padded.

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 full schema coverage, rich annotations, and an output schema, the description only needs to convey intent and routing; it does that well and even summarises the capped result shape. What remains thin is the relationship to twin_cities_datasets and twin_cities_lookup, which an agent choosing among 15 siblings would want.

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 baseline is 3. The description's address guidance ('to answer about one property and its surroundings') largely restates the schema's own wording for `address`, and `scope`, `columns`, and `dataset` are left entirely to the schema. It adds little beyond the structured fields.

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 — 'answers a question about the Minneapolis-St. Paul metro from joined public records' — and enumerates the record types it joins (sales, ownership, adjacency, contamination files, licensing, census). It never names the neighbouring tools (twin_cities_datasets, twin_cities_lookup), so sibling differentiation is left to inference, though the 'joined public records' framing implies it is the query layer over the catalog.

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 an explicit branch rule: 'Give an `address` to answer about one property and its surroundings; omit it to ask about the whole market cut.' The three example invocations further ground when the tool applies. No exclusions or named alternatives against siblings are given, so it stops short of a 5.

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