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

Annotations already convey read-only, idempotent, and non-destructive behavior. The description adds a useful behavioral constraint: up to 100 queries per call, and discloses what the tool returns. This goes beyond what the annotations provide.

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?

The description is two sentences with no filler. The core purpose and return fields are front-loaded, followed by the capacity constraint. Every sentence provides useful information.

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 tool with 7 parameters, no schema descriptions, and no output schema, the description is incomplete. It explains the main purpose and output fields but does not clarify parameter formats, defaults, pagination semantics, or date/period behavior, which are needed for reliable invocation.

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 0%, so the description must compensate. It only adds meaning for 'consultas' via the 100-query limit; the other six parameters ('pais', 'local', 'idioma', 'limite', 'pagina', 'periodo') receive no explanation, and the enumeration values are left undefined.

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 specific verb 'Busca imagens' and resource 'Google imagens', distinguishing it from the sibling search tools. It also lists concrete return values: image URL, thumbnail, dimensions, and source page.

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 is clear that this tool is for Google image searches, and the capacity limit 'Aceita ate 100 consultas por chamada' adds practical usage context. It does not explicitly mention exclusions or alternatives, but the resource and output make the appropriate use case obvious.

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