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

With no annotations, the description carries the full burden and does well: it discloses the data provenance, the 100+ monthly-arrival existence threshold for quiet mode, and the important caveat that monthly patterns may not reflect point-in-time congestion. It does not cover ordering stability, pagination, or return shape, which keeps it short of a 5.

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?

Dense but front-loaded: mode semantics and the quiet-use-case lead before the category and caveat details. Every clause carries information, though the single long paragraph could be broken into clearer segments.

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 5-parameter, no-annotation, no-output-schema tool, the description supplies source, metric, mode logic, and a user-facing caveat instruction. The main omission is any indication of the return format or result structure, which an agent must infer.

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 baseline is 3, but the description adds meaning beyond the schema — the rationale and threshold behind mode='quiet', concrete category examples, and what list_categories=true returns. This goes past restating the field descriptions.

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 (find less crowded or most crowded places in Jeju) and distinguishes the two operating modes up front. The source and metric (big-data platform, per-destination navigation arrivals, tourist/resident split, monthly) make it unmistakable what the tool returns.

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?

Explicitly says mode='quiet' is for finding quiet alternatives to crowded attractions and that mode='busy' ranks by tourist arrivals, which is genuine when-to-use guidance. It also points to list_categories=true for the full category list, though it does not contrast against any sibling tool.

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