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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so safety is partly covered. The description adds only that validation occurs before a 'governed' gateway call, but does not say whether the call is actually made, how validation failures behave, or what errors or rate limits apply.

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 definition is a single front-loaded sentence with no filler. It is appropriately concise, though the brevity contributes to under-specification for a router-style tool with 24 enumerated targets.

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?

This is a complex nested dispatcher with an enum of 24 Mercado tools and no output schema, but the description does not explain validation rules, dispatch behavior, expected return values, or error handling. For a tool of this complexity, the description is substantially incomplete.

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%, with toolName fully enumerated and arguments described generically. The description adds the relationship between validating a selected tool and its required arguments, but does not explain per-tool argument requirements beyond what the schema already provides.

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 a specific action: validating a selected tool and its required arguments before calling a gateway. However, it does not clarify why this is called 'product selection' or distinguish it from sibling tools such as nexscope_data_mercado_product_selection or nexscope_mercado_market_intelligence.

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 explicit guidance on when to use this tool versus alternatives, nor any prerequisites or exclusions. The schema implies it is a dispatcher for Mercado tools, but the description does not state that routing rule or when validation should happen.

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