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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds one genuinely useful behavioral fact — that results are restricted to cities with an active/playable channel — but says nothing about pagination, ordering, or result size.

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?

A single sentence with no waste, and the scope qualifier is front-loaded before the filter list. Slightly terse phrasing makes the 'canal tocável' constraint less immediately parseable, but structurally it is efficient.

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 two-param, fully documented, read-only list tool this is close to adequate, and annotations carry the safety profile. However, with no output schema and no mention of result size, ordering, or pagination, an agent can't anticipate the return shape; the Portuguese text against an otherwise English toolset is also mildly jarring.

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 description mentions filtering by country and by state/subdivision, which mirrors the two schema parameters, but adds no syntax, default, or combinability details beyond what the schema already documents at 100% coverage. Baseline 3 applies when the schema carries parameter semantics.

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 names the resource (cities) and a meaningful scope constraint — only cities that have a playable/touchable channel — plus the two axes of filtering. That verb+resource+scope is clear, but it never mentions sibling tools like list_countries or list_subdivisions, so the agent gets no explicit differentiation.

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 statement of when to use this versus the many sibling listers (list_countries, list_subdivisions, list_networks). The filtering axes are implied as usage but no condition or alternative is spelled out.

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