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

No annotations are provided, and the description does not disclose any behavioral traits such as read-only nature, potential side effects, rate limits, or output characteristics. The description only hints at data content without saying what happens when called.

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 description is extremely short, which is superficially concise, but it is under-specified to the point of being unhelpful. It lacks necessary details and front-loads a vague subject instead of a clear call to action.

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, no annotations, and minimal parameter documentation, the description fails to provide the necessary context for an agent to call this tool correctly. Even a single-parameter tool needs to clarify input semantics and expected output.

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 sole parameter 'slug' is completely undocumented in the schema (0% coverage). The description does not explain what 'slug' refers to (e.g., genre identifier, item ID) or its format, leaving the agent to guess.

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 is a noun phrase describing content ('Daily time series of genre – median and p90 of quantity per 10,000 yen') with no explicit verb or action. It is unclear whether the tool retrieves, computes, or lists this data. It also does not distinguish itself from the many sibling tools (e.g., furusato_index, furusato_hitorigurashi) which likely also deal with time-series or genre data.

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 versus its siblings. Given the large sibling list, an agent has no clue about the intended context or selection criteria, making it impossible to route correctly.

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