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

Annotations already cover readOnly, idempotent and non-destructive, so the bar is lower, and the description still adds real context: live pricing, PHP currency, parity with the myboracayguide.com booking form, and that discounts are already applied. It stops short of stating whether the price is cached or can change between calls, or what the returned figure looks like.

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, no filler, and the core purpose is front-loaded before the currency, price-parity and no-booking caveats. Every clause carries information an agent needs.

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 read-only pricing tool with no output schema and fully documented parameters, the description covers purpose, currency, pricing basis and side-effect-free behavior. The one gap is that it never indicates whether the response is a single total or a per-passenger-type breakdown, which an agent might need to present results.

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 earns a step up by synthesizing that price is driven by package, trip type, airport and passenger mix, telling the agent which inputs actually move the number. It adds no format or default guidance beyond that, but the schema already carries defaults and enums.

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 and resource ('Get the live price ... for a Boracay airport transfer') plus the dimensions that define the quote (package, trip type, airport, passengers). The closing 'Books nothing' explicitly separates it from the sibling create_boracay_transfer_booking_link, so an agent can route without opening a schema.

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?

'Books nothing' implies this is the quoting step before booking, but the description never names create_boracay_transfer_booking_link or list_boracay_airport_transfers as the follow-up/preceding calls. The package-name prerequisite exists only in the schema description, not the tool description, so usage is implied rather than stated.

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