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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the scoping ('do usuário') and the returned fields (ids and limits), but does not disclose any additional behavioral traits such as pagination, ordering, or whether inactive cards are included. This is acceptable for a simple read-only list, but adds only modest extra context.

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 a single, compact sentence in Portuguese that front-loads the action and resource, followed by the relevant output fields. Every word earns its place and there is no redundancy or filler.

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?

Given the tool's low complexity (no parameters, no output schema, no nested objects) and strong annotations, the description is largely complete. It states what the tool returns (ids and limits) and the scope (user's cards). Minor omissions like pagination or sorting are not critical for this kind of list operation, so a slight deduction is appropriate.

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 schema description coverage is 100%. With no parameters, the description has no obligation to explain parameter semantics, and the baseline of 4 applies. It correctly omits any parameter-related information.

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 'Lists the user's credit cards with ids and limits' uses a specific verb (list), a specific resource (credit cards), and states the output fields (ids and limits). This clearly distinguishes it from sibling list tools like organizze_list_accounts and from credit-card-specific operations like create/update/credit card or get_invoice.

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 provides no guidance on when to use this tool versus alternatives. It does not mention exclusions, prerequisites, or conditions under which a different listing or credit-card tool should be chosen. The usage context is only implied by the verb and resource.

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