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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered without the description. The description adds real behavioral context beyond that: the result is capped at 10 services and is scoped to exactly one category. It does not describe the shape of the comparison output, which is the main remaining gap.

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 short sentences with the operation and scope front-loaded; nothing is padded. The Korean sentence is a direct translation of the English one, which doubles length without adding information, though it is defensible for a Korean-market tool.

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?

With no output schema, the description usefully states what the comparison covers (Korean UI, KRW pricing, starting price, trial conditions), which is exactly what an agent needs to decide whether this satisfies a request. Only the result structure beyond those dimensions is unaddressed, a minor gap for a read-only tool.

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 67%: category is documented as a slug pointing at list_categories, but sort only defines its 'korean' value and leaves 'popular' and 'pricing' unexplained, and limit has no prose. The description contributes the 10-service ceiling (matching limit's maximum) and confirms the single-category constraint, but does not clarify the unresolved sort enum values.

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?

Names a specific verb (compare) and resource (top AI services in one secondary category) and enumerates the comparison dimensions (Korean UI, KRW pricing, starting price, trial conditions). The 'compare' framing naturally separates it from search_ai_services and get_ai_service, but it never names a sibling or states what it is not, so differentiation is inferred rather than explicit.

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?

Usage is implied: reach for this when you need a side-by-side comparison within a single secondary category. There is no explicit when-not guidance and no mention of find_alternatives or search_ai_services as alternatives for adjacent needs, leaving the agent to infer the boundary.

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