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

Annotations already declare readOnly, idempotent, non-destructive and openWorld=false, so the safety profile is covered. The description adds genuinely useful context beyond that: results are distance-annotated in metres and come from a curated (closed) dataset, consistent with openWorldHint. It does not say how results are ordered, what an empty radius returns, or whether there is any cap beyond the schema's limit.

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?

A single sentence with no filler, and the resource and unit of measurement are front-loaded. Slightly awkward phrasing ('to a WGS84 coordinate supplied in the request') is the only blemish.

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 carries the full burden of describing returns, and it only gives the distance field and unit; ordering (nearest-first is implied but unstated), result shape, and behaviour on empty results are missing. For a five-parameter read tool this is adequate but not 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 coverage is 40%: limit and radius are documented in the schema, while latitude, longitude and category are bare. The description compensates partially by specifying the coordinate reference system (WGS84), which is real added meaning for the two undocumented required params. However, it says nothing about the category enum's filtering behaviour or its default.

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 (find nearest), resource (curated Kensington places) and the key input (WGS84 coordinate) plus the unit returned (metres). It clearly reads as a proximity lookup, which implicitly separates it from search_places or list_places, but no sibling is named, so differentiation requires inference.

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?

There is no explicit when-to-use, when-not-to-use, or named alternative among the six siblings. The phrase 'to a coordinate supplied in the request' hints that coordinates are the precondition, but the agent must infer why it would pick this over search_places or get_place.

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