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

Annotations show readOnlyHint=false and destructiveHint=false. The description states 'Mutações' (mutations), which is consistent, but does not add value beyond annotations. No details on side effects, prerequisites, or error cases are provided.

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 uses a bullet list format but includes irrelevant actions. It is not concise for the specific tool; it could be reduced to a single sentence about changing the due day. The final note about flattened action is helpful but does not compensate for verbosity.

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 7 parameters, 0 required, 0% schema coverage, no output schema, and nested objects, the description is severely incomplete. It does not specify required parameters for change_due_day, explain the data object, or describe the response. An agent cannot reliably use this tool.

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 coverage is 0%. The description lists parameters (subscriber_code, due_day, etc.) but does not clarify which are relevant for change_due_day. It includes parameters for other actions, causing confusion. No explanation of nested objects or expected values.

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 multiple actions (cancel, reactivate, change_due_day, switch_plan), but the tool name and final note 'Flattened action: change_due_day' indicate it is specifically for changing the due day. This is confusing and leads to ambiguous purpose.

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?

No guidance on when to use this tool vs. alternatives. Sibling tools like hotmart_subscriptions_write_cancel and hotmart_subscriptions_write_reactivate exist, but the description does not direct the agent to use them. Including unrelated actions in the description misleads agents.

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