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

With no annotations, the description carries the full burden, and it provides substantive scope: data comes from the Ministry of Finance, is daily, covers 10-year and 1-year JGB yields, and spans from 1974 onward. It does not disclose units or the exact return shape, but it is far beyond a bare label.

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 compact sentences convey source, maturities, frequency, start date, and intended use with no redundant detail. The topic is front-loaded and every clause earns its place.

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 no-parameter data tool with no output schema, the description is complete: it states what data, from whom, at what frequency, since when, and for what purpose. The absence of explicit units or response format is minor given the tool's simplicity.

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?

The tool has zero parameters and the schema is empty, so the baseline is 4; there are no parameter semantics for the description to add. The description instead clarifies the data content, which is useful context.

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 clearly identifies the tool as a source of Japanese Ministry of Finance government bond yields, specifying 10-year and 1-year maturities, daily frequency, and a start year of 1974. It is not a tautology, but it lacks an explicit action verb and does not contrast with sibling tools such as chingin or hikaku.

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 closing phrase '住宅ローンや預金金利の背景' gives a concrete usage context: the data is relevant as background for mortgage and deposit rate questions. It does not, however, name alternatives or state when not to use this tool.

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