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

The description labels the tool as "não-destrutivas" (non-destructive), which aligns with destructiveHint=false in annotations. However, it does not disclose additional behavioral traits such as required permissions, side effects on other resources, or idempotency beyond what annotations already 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 cluttered with a list of actions for a multi-action tool, even though this tool represents only one action. Important details (requirements, bulk support) are buried. A more focused description for this specific action would be more concise and efficient.

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 has no output schema and limited parameter documentation. The description specifies required parameters for the action and mentions bulk support, but does not explain the expected return value or the structure of the 'data' field. Given the complexity of payment operations, more completeness is needed.

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?

With 0% schema description coverage, the description helps by stating that for this action, subscription_id and data are required. However, it does not explain what the 'data' string should contain (e.g., payment method fields). The schema lists all params as optional, creating a slight inconsistency with the description's requirement statement.

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 title and description clearly indicate this tool updates the payment method of a Pagar.me subscription ("update_payment_method"). The description lists multiple actions but singles out this one as the flattened action. It distinguishes from sibling tools like pagarme_subscriptions_write_create or pagarme_subscriptions_write_update_card.

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 lacks explicit guidance on when to use this tool versus alternatives. It mentions bulk support but does not state prerequisites, conditions, or when not to use it. No comparisons to siblings are provided.

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