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

No annotations are provided, so the description carries the full burden, and it discloses only that the data originates from 地価公示. It says nothing about whether the result is a single prefecture-wide average or a list of points, what unit or year the price reflects, rate limits, or whether the call is read-only.

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?

The single parenthetical phrase is tight and front-loaded with the resource, but it is under-specified rather than genuinely concise. Nothing is wasted, yet almost everything an agent needs is absent.

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 tool with no output schema and no annotations, the description is minimal but not hopeless: the resource and source are identifiable. However, missing code format, unit, and output shape leaves real gaps for an agent to trip over.

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 description coverage is 0% and the single parameter 'prefecture_code' is an untyped-format string with no enum or pattern. The description only implies that the parameter identifies a prefecture; it never states whether the expected value is a JIS code like '13', a name like 'Tokyo', or '東京都' — the most likely source of a failed call.

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?

The description names a specific resource and aggregation ('average land price by prefecture') plus the provenance (National Land Numerical Information, Land Price Public Notice), so the agent knows exactly what data comes back. It does not differentiate from any sibling, though no sibling in the list covers land prices, so confusion risk is low.

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?

There is no guidance on when to use this tool, no prerequisites, and no mention of alternatives among the sixteen jp_* siblings. The agent must infer that this is the land-price lookup purely from the name.

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