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

Annotations already cover readOnlyHint, idempotentHint, and destructiveHint, so safety is established. The description adds behavioral context by sourcing values from the 'SnowSure conditions resolver/contract' and noting 'live conditions', which implies data freshness. This goes beyond annotations without contradicting them.

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?

The description is three sentences with zero filler: it fronts the core purpose, then usage context, then the optional restriction. Every sentence contributes unique value, and the structure is scannable for an agent.

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?

Given the output schema exists (so return format is documented elsewhere), annotations cover safety, and the schema fully explains both parameters, the description is complete for proper tool invocation. It covers what the tool does, when to use it, and data provenance—nothing needed for correct usage is missing.

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% — both `slugs` and `dimensions` are fully described in the schema (including an example for slugs and an explicit list of dimension values). The description adds little beyond restating the optional restriction, so it does not materially enhance parameter understanding beyond the schema.

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 ('Compare'), a specific resource ('resorts'), and a precise scope ('2–4 resorts side by side across snow, terrain, and live conditions'). It also provides concrete example queries that clarify intent, and clearly distinguishes itself from sibling tools like compare_forecasts and compare_passes by focusing on resort attributes.

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?

The description explicitly frames when to use the tool: 'Use for head-to-head stat questions phrased as either/or' with multiple examples. It does not name alternatives or exclusions (e.g., when to use compare_passes instead), but the provided context is clear enough that an agent can infer applicability from the examples and sibling names.

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