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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description still adds real value by disclosing the return shape (indicator code, levels, time grain, source, licence, link) and the composite code convention for news topics — content an agent cannot get from the schema. It does not mention result size or whether the optional app filter alters the payload.

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 the resource name and domain coverage, then the return contents, then the call-to-action. The enumeration of app categories is dense but does real work by telling the agent whether its topic area is covered.

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 carries the return-value burden and does so (views, codes, levels, grain, source, licence, link). It also supplies the cross-tool relationship that makes the output actionable. Nothing essential for correct invocation is missing.

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% and the single `app` parameter is already documented, so the baseline is 3. The description goes slightly further by illustrating what an app/view code looks like, which helps an agent infer the values the `app` key accepts, though it never states that the parameter maps to that code.

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 (lists) and resource (each Map App's views) and immediately characterizes the domain coverage. It explicitly separates itself from siblings by naming get_statistic and rank_regions as the consumers of the indicator codes it exposes.

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 a concrete trigger — use it to learn the indicator codes that get_statistic and rank_regions require — and shows the code format via the news-topic example ("news_topic_share:world-conflict"). This is explicit when-to-use with named downstream alternatives rather than implied context.

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