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

Goes well beyond the annotations (readOnly=false, destructive=false, openWorld=true) by disclosing that the total is shown before payment, that extra authentication halts the call and returns a completion link, that confirmation is on by default but toggleable, that it reaches other people, and that a Cotlet API key with app access is required.

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 core action and return value, then layers behavioral detail without filler. It is dense but every sentence carries operational information, though the KlookCash eligibility list makes it longer than strictly minimal.

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 complex, open-world, no-output-schema booking tool, the description compensates by naming the return value (Booking Reference ID), the authentication fallback, the confirmation policy, and the credential requirement. An agent has enough to invoke and interpret it correctly.

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 100% schema coverage the baseline is 3, but the description adds real meaning beyond the schema for use_klookcash: how it ticks the Discount section and its eligibility limits (>=10 KlookCash, not on Passes, e-Gift Cards, Travel Insurance, Stay+ or selected events). Other parameters are largely left 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 (Book) and resource (a package of an activity for a date and time slot), and specifies the returned artifact (Booking Reference ID). This clearly separates it from sibling read/amend/cancel tools like klook_get_booking, klook_amend_booking, and klook_cancel_booking.

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?

The description establishes when the tool applies (booking one package for a date/time slot via Klook checkout) and conditions the use_klookcash option. It does not explicitly route the agent to prerequisite siblings such as check_availability or get_activity, so context is clear but not exhaustively signposted.

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