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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), so the bar is lower. The description still adds real behavioral value: it discloses that distances are straight-line (not travel distance) and that lift counts are an opt-in live fetch, implying extra per-resort requests and latency beyond the schema's terse note.

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?

Two short sentences with no filler; the core spatial semantics are front-loaded and the optional behavior is appended as a secondary clause.

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 should convey what comes back; it identifies the ordering metric and the optional status enrichment, which is close to sufficient. Missing pieces are minor: tie-breaking, whether results include distance values, and the cost of the optional live fetch.

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 only 40%: max_km and include_status are documented in the schema, while latitude, longitude, and limit carry no descriptions. The description implies sorting by distance and an optional status fetch, but adds no units, ordering, or result-count semantics beyond what the schema already states.

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 the resource (resorts), the spatial criterion (closest to a point), and the metric (straight-line distance), which is enough to separate it from name-based siblings like ski_search_resorts. It lacks an explicit verb and never names a sibling, so an agent must infer the contrast rather than read it.

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?

Usage is implied: this is the tool for proximity queries when you have coordinates, as opposed to search or status tools. However, there is no explicit when-to-use statement, no exclusion (e.g. 'do not use for name search'), and no mention of alternatives such as ski_search_resorts or ski_compare_resorts.

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