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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the safety profile is covered. The description adds the specific data fields returned (points, wins, etc.) and the example, providing useful behavioral context beyond what annotations offer. No contradiction exists.

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?

Two short sentences: the first defines the resource and content, the second gives a direct usage example. No filler or redundancy. Front-loaded with the core purpose.

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?

The tool is simple with a single parameter and no output schema. The description explains what data is returned and provides a usage example, covering the essentials. It could mention whether a group is required, but given low complexity, it is sufficiently complete.

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 0% for the 'group' parameter, so the description must compensate. It gives an example ('grupo C') implying the parameter is a group identifier, but does not specify format, allowed values, or whether it's optional. This is marginal but better than nothing, hence a 3.

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 clearly states the tool returns group standings (classificação) with specific fields (points, games, wins, draws, losses, goal difference). It also provides an example query ('como está a tabela do grupo C') that clarifies the resource. This distinguishes it from siblings like worldcup_groups or worldcup_matches, making the purpose unambiguous.

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?

The description explicitly says 'Use para ...' with an example, giving a clear when-to-use context. It does not mention when not to use or name alternative tools, but the example strongly implies usage for group standings queries. Given the sibling set, this is adequate guidance.

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