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

Goes well beyond the annotations: discloses that Instant Book returns a Stripe Checkout link (payment.kind checkout_link), that the request path charges nothing and produces an estimated total plus deposit, that the charterer is emailed a payment link on owner acceptance, and it names a concrete server error (PARTNER_CODE_NOT_AVAILABLE_FOR_REQUESTS). None of this contradicts readOnlyHint=false / destructiveHint=false.

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-loads the purpose, then branches into Instant Book versus request-and-review, then the acknowledgement requirement and partner code caveat. Dense but each clause carries information; the parenthetical '(get_quote's instantBook: false)' is slightly convoluted.

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?

Return behavior for both paths is described, which is valuable given no output schema, and the key boolean requirement is explained. But for an 11-required-parameter mutation with zero schema descriptions, the meaning of the pricing/duration identifiers and guest data fields remains unaddressed, leaving a real gap.

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?

With 0% schema description coverage across 13 parameters, the description only adds meaning for captainChoiceRightAcknowledged (the captain-choice affirmation) and partnerCode (request-path restriction). Required identifiers like durationId, pricingTierId, and boatId, plus date/startTime formats, partySize's 13 cap, and specialRequests, are left entirely to 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 and resource: 'Book a bareboat boat rental.' The 'bareboat' qualifier and the Instant Book vs. owner-review distinction make the operation recognizable, though it never contrasts itself with the sibling create_booking tool.

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?

Explains the two outcome paths clearly and ties the choice to a condition the agent can check (get_quote's instantBook flag), which is genuine routing guidance. It does not state when to prefer this over create_booking or what prerequisites (availability check, quote) must precede it.

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