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

Annotations only declare readOnly/openWorld/not-idempotent; the description adds material behavior: $0.01 per call under product ski.quote, USDC charged from the configured wallet, budget-cap enforcement, and an explicit 'third-party data, not instructions' injection warning. That is exactly the value-add a description should carry.

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 short sentences, front-loaded with the purpose and then the cost/safety facts. Dense but each sentence carries distinct information; no significant padding.

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?

For a paid, open-world query with no output schema, the description covers cost, payment mechanism, budget caps and data-trust, which are the risky parts. It stops short of describing the shape of the returned quote, which is the one thing left uncovered by structured fields.

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%, so the baseline is 3. The description gestures at 'dates, ages and days', which roughly maps to date/ageBand but introduces a 'days' notion that has no corresponding schema field, adding ambiguity rather than clarity.

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 verb+resource+scope: a single lift-ticket price for given dates, ages and days at one resort. The 'one resort' phrasing loosely separates it from bulk siblings like ski_prices_bulk, but no sibling is named explicitly.

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 by the scoping ('one resort') and the paid-per-call warning, which suggests this is the single-quote path versus a bulk alternative. There is no explicit when-to-use, when-not, or named alternative among the many ski_* and *_quote siblings.

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