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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It merely says 'Discover' without stating whether this is a read-only operation, what the response contains, whether authentication is required, or what side effects might occur. This is effectively no behavioral transparency.

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 extremely short and front-loaded, but it is under-specified rather than concise. One vague sentence does not earn its place because it provides almost no operational value to an agent.

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 annotations, no output schema, and a vague one-line description, the tool is not adequately described. An agent cannot determine what the tool returns, when to call it, or how it differs from siblings, making the definition functionally 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?

The tool has zero parameters and the schema is empty, so there is nothing to explain. With 0 params, the baseline is 4; the description does not need to add 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 says 'Descobre a API Grade' ('Discover the API Grade'), which combines a verb with a resource but leaves 'API Grade' undefined. The tool name 'api_index' suggests an index of endpoints, but the description does not clarify what the tool actually returns or how it relates to sibling tools.

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 guidance on when to use this tool versus any of the many sibling tools. The description provides no context or routing cues, such as 'use this to list all available endpoints' or 'use this instead of searching individual endpoints.'

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