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

No annotations are provided, so the description carries the full disclosure burden. It does add real behavioral detail the schema lacks: the omit-for-latest default and the rule that a bare year on a semester indicator resolves to the latest period in that year. It says nothing about read-only safety, error behavior for unknown indicators/periods, or result shape beyond the national figure.

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?

Three sentences, front-loaded with what the call returns and why, followed by the period rules and the edge case. Dense but every clause carries information; no filler.

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 and no annotations, the description should do more to describe the returned payload (region set, units, how the national figure is represented) and failure modes. It covers input semantics well and hints at return contents, which is adequate but leaves the response contract underspecified for a two-param data 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 100%, so the schema already documents both params and the baseline is 3. The description adds meaning beyond it: period accepts YYYY or YYYY-MM, omission means latest, the format source is list_stat_indicators, and year-only input resolves against semester indicators.

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 and resource plus the exact scope: one indicator, one period, all regions, plus the national figure, with '(for a map)' clarifying the use case. It never names the sibling get_stat_series, so the distinction between a cross-region snapshot and a time series is left for the agent to infer from the scope wording.

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?

Gives clear operating context: use for a map, period is YYYY or YYYY-MM as listed by list_stat_indicators, omit it for the latest. It does not explicitly say when to prefer it over get_stat_series or point at list_stat_indicators as the source of valid indicator ids.

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