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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuine value beyond them by disclosing the return shape (image plus a stable, cacheable, embeddable public URL), which is exactly the context an agent needs for a render tool.

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?

One dense sentence, front-loaded with the artifact type and its return payload. Every clause carries information, though the enumerated view descriptions make it slightly long for a single sentence.

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 burden of describing the return and does so (image + stable public URL). Combined with 80% schema coverage and full annotations, an agent has enough to invoke it correctly, though metric semantics and error behavior remain implicit.

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 80%, so a baseline of 3 applies, but the description goes further by explaining that view=card shows 5 past + 10 future days with a best-day callout and view=week is a 7-day calendar, and that leaderboards apply to region, state or all resorts. It does not clarify the metric enum or the id format, leaving small gaps.

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 artifact (a branded PNG snow card) and enumerates the three render modes it produces (card, week, leaderboard), so an agent can distinguish it from data-returning siblings like get_resort_snow. The verb+resource+scope are unambiguous.

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?

Explains that the output can be looked at or shown to the user and maps each view/kind combination to what gets drawn, giving clear selection context. It stops short of explicitly naming when to prefer this over get_resort_snow or get_top_snowfall (e.g., 'use when the user wants a visual rather than data').

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