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

Far exceeds the annotations (which only flag readOnly=false, openWorld=true, idempotent=false): it discloses the exact cost ($0.01/call, product id), the payment channel (USDC from configured wallet), budget-cap enforcement, that results are third-party data not instructions (prompt-injection safety), and the confirm_over_cap behavior. This is unusually rich behavioral context for a paid 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?

Front-loaded with the resource definition, then pricing, then safety, then the free alternative. Dense and nearly waste-free, though the telegraphic 'PAID:'/'Price $0.01 per call (product ski.inventory)' pairing is mildly redundant.

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 still covers the essentials an agent needs: what it returns, the cost, the payment mechanism, and the free preview alternative. It does not describe result shape or pagination, but nothing critical to correct invocation 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 coverage is 100%, so the baseline is 3. The description adds real meaning by tying calls to 'budget caps' and framing payment semantics that contextualize confirm_over_cap, though it does not explain country/state formats (the schema already does).

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 concrete resource and scope: 'Lifts and runs of a ski area as mapped.' An agent can tell it returns inventory data rather than prices or operator details. It does not, however, explicitly distinguish itself from the many sibling ski_* tools, so it stops short of a 5.

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?

Gives clear contextual guidance: this is a paid call and the agent should use free_sample first to see a real answer for free. That is actionable routing. It lacks an explicit when-not condition or a named alternative for the price/operator questions handled by siblings.

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