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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety bar is low; the description adds real value by naming the data source (OpenStreetMap) and the fields returned (address, coordinates, opening hours, website, phone). The 'when known' qualifier usefully signals that fields are sparse/optional, though coverage limits and the 40-result ceiling are not mentioned.

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?

Three front-loaded lines: what it does, when to use it, and a literal example. The category enumeration is long but earns its place by settling the ambiguity of 'one kind', and nothing is repeated from the schema verbatim.

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 listing returned fields, and the annotations cover the safety profile. For a 4-parameter read-only lookup, the only residual gap — explicit routing away from places_near — is minor.

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 75% and the schema itself documents what/where/lang well; the description's example payload {"what":"restaurant","where":"Rome","limit":10} makes the expected input shape immediately usable and reinforces that 'what' is a single category rather than a list. The 'in English or another language' hint also echoes flexibility the schema only partly conveys for lang.

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 plus resource: finds places of one category in a city/area, sourced from OpenStreetMap, with a concrete enumeration of supported categories. It is clear what it does, but it never distinguishes itself from the sibling places_near (coordinate-based lookup) or geocode_address, so an agent must infer the boundary.

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?

A dedicated 'Use when' line with three natural-language triggers ("restaurants in Rome", "museums in Amsterdam", "a pharmacy in Brussels") gives strong positive guidance. There are no exclusions or named alternatives, so the when-not case versus places_near 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.