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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the read-only safety profile is covered. The description adds churn-specific behavior and aggregate metrics, but does not disclose return structure, pagination behavior, or how 'value at risk' is computed.

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 that communicates scope, outputs, and optional filters without filler. It is front-loaded with the core concept ('Assinaturas perdidas'), though it does not use structure to separate list, metrics, and filter details.

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 output schema, the description bears more responsibility for return-value expectations, but it only vaguely names metrics and does not explain fields, date formats, account scoping, or the relationship to sibling subscription tools. An agent would still need to infer several details before calling it confidently.

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 0%, so the description must compensate. It only mentions optional period filters, roughly covering start_date and end_date, but leaves page and account unexplained, and provides no format or semantics for any parameter.

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 clearly identifies the resource as lost/canceled/inactive subscriptions and states the concrete outputs: a list plus aggregate metrics (value at risk, affected customer count). This distinguishes it from generic subscription tools like cakto_subscriptions_list, though it does not name or contrast the sibling explicitly.

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 tool's purpose implies it is used for churn analysis, and the optional period filters give context. However, there is no explicit guidance on when to prefer this over cakto_subscriptions_list or cakto_subscriptions_get, and no exclusions or fallback conditions are stated.

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