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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the description is not the sole source of the safety profile. It still adds real value beyond them: 'nothing is booked' clarifies the business consequence, the 'call for quote' fallback explains a non-numeric price outcome, and the returned fields (route, miles, transit days, 3-day pickup window) describe the response shape.

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 definition is front-loaded: purpose, then triggering condition, then return contents, then the modification vocabulary. The long comma-separated modification list is dense but justified, as it is the only documentation of those accepted values.

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?

An output schema exists, so return values need not be fully spelled out, and the description does summarize them. However, for a 13-parameter tool with no per-parameter schema documentation, the definition should clarify the optional inputs (operability, lift inches, personal items weight, earliest pickup date) that materially affect price.

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 0% across 13 parameters, so the description carries a heavy burden. It partly compensates by enumerating all accepted modification values — information that exists nowhere in the schema, since 'modifications' has no enum — and by naming open/enclosed as transport choices, but it leaves operable, lift_inches, personal_items_lbs, first_available_date, trim and other_modification unexplained.

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 gives a specific verb and resource — 'Estimate the price to ship a car ... between two US locations' — plus the provider name, so an agent knows exactly what this tool computes. It is unmistakable against the only sibling, request_callback, which handles human follow-up rather than quoting.

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?

'Use when the user asks what it costs to ship or transport a vehicle' states a clear triggering condition. There are no explicit exclusions or a named alternative for cases like a quote that needs human judgment, though the description does hint at this by mentioning 'call for quote' outputs and a booking link.

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