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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with 'stateless price preview and does not save the selection.' It adds genuinely useful behavior beyond the annotations: the server is the single source of truth for prices and the LLM must never compute totals. It omits return-shape specifics, though for a preview tool the transparency is strong.

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 core purpose and the pricing-authority warning are front-loaded, and each sentence carries actionable instruction. It is slightly longer than strictly necessary but no sentence is filler, so structure is efficient.

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 stateless preview tool with no output schema, the description tells the agent to present 'the complete updated summary returned by the server,' which compensates for the absent output schema. Combined with the source-of-truth and statelessness notes, an agent has enough to call it correctly; only the distinction from the booking_detail sibling 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 schema already documents each parameter. The description nonetheless adds real meaning by explaining that id_boat and id_tbf1 must be copied from search_boats and that selected_extras, pax, currency, ports and payment options are the inputs to be sent. This provenance guidance is not present in the schema.

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: 'Apply customer selections and return server-recalculated booking details,' which tells the agent this is a recalculation/preview step. It names sibling tools search_boats and booking_create as data sources and next step, but does not differentiate from the near-identical sibling 'booking_detail', leaving ambiguity about which variant to pick.

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 preconditions: copy id_boat and id_tbf1 from search_boats, and repeat the full selected_extras list in booking_create if the customer proceeds. It also clarifies this is a preview step that does not save. It stops short of stating when to choose this over the sibling booking_detail variant.

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