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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered; the description adds that results are cross-vertical and carry both a normalized type and Klook's raw type code, which tells the agent how to interpret heterogeneous rows. It stops short of behavioral detail the annotations don't cover, such as result caps, ranking, or whether empty/short queries degrade gracefully — though the 1-80 character rule is stated.

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?

Two sentences, front-loaded with purpose before routing. The enumeration of return fields (normalized type, title, subtitle, icon, landing URL, raw type code) is partly duplicative of the output schema and makes the first sentence dense, which is the only real cost.

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 one-parameter read-only suggest tool with full schema coverage, an output schema, and annotations, nothing an agent needs is missing: purpose, input constraint, result composition, and sibling routing are all present.

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?

Only one parameter, and the schema already documents it at 100% coverage including the 1-80 character bound. The description's contribution is calling it a "partial query" for suggestions, which reinforces prefix-style matching rather than full-string search, but that meaning is also present in the schema wording. Baseline 3 is appropriate.

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?

Uses a specific verb and resource ("Return Klook's cross-vertical search-box suggestions for a partial query") and then enumerates the four suggestion kinds (destination, keyword, vertical-service, activities) with the fields attached to each. An agent can distinguish this unified suggest from klook_suggest, klook_attractions_suggest, and klook_search without opening any 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?

Gives an explicit selection rule: use this when you don't yet know which Klook vertical a name belongs to, and names three concrete alternatives with the condition that selects each (activities/cities for tours or attractions → klook_suggest or klook_attractions_suggest; an actual result page → klook_search). Both the when-to-use and the when-to-use-something-else are stated.

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