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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine behavioral context beyond that: the upstream data sources, the fact that a recent series is returned alongside the value, and the default-to-latest period behavior.

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?

It is a single dense sentence followed by a short clarifier, front-loading the resource scope before the return contents and the code conventions. Information-dense but every clause carries substance; it could be split for readability but nothing is wasted.

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, the description correctly compensates by listing the returned fields (value, period, rank, US figure, source, licence, series) and the data providers. It lacks any note on error or missing-data behavior, which is the only real gap for a 4-parameter lookup 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 description coverage is 100%, so baseline is 3; the description goes slightly beyond by explaining where indicator codes originate (list_map_apps) and clarifying the interaction between indicator and topic for news shares, which the schema presents as independent properties.

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 states precisely what is retrieved (one statistic for one country, US state, county or congressional district) and enumerates the returned content (value, period, rank, US figure, source, licence, series). It is far more specific than the title alone and implicitly separates itself from rank_regions, though it never names a sibling to sharpen the distinction.

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?

It gives a concrete prerequisite by routing the agent to list_map_apps for indicator codes, and explains the news_topic_share:<topic> vs. separate topic argument path. It stops short of an explicit when-not-to-use statement or a named alternative for multi-place ranking.

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