add_subscription_rate_plan_charge

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

With no annotations, the description carries the burden of disclosing behavior. It indicates the operation is a POST (mutation), lists required and conditional fields, and notes a specific transformation (weight multiplied by 100). It does not mention side effects, authorization, or rate limits, but covers essential behavioral aspects adequately.

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 moderately long but efficiently organized: action, endpoint, required fields, conditional rules. It is front-loaded with the purpose. A slight improvement could be grouping fields or providing an example, but it remains clear and to-the-point.

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 17 parameters, the description covers required and conditional fields. However, it does not explain the return value (e.g., the created charge object) or provide examples. For a complex creation tool, mentioning response format or expected outcome would improve completeness.

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 100%, so baseline is 3. The description adds: weight conversion detail, conditional requirement for billingPeriodAlignment and specificBillingPeriod when chargeType is recurring, and inline enumeration of valid values. This exceeds baseline by providing extra meaning.

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 states the action ('Add a rate plan charge to a subscription rate plan') and includes the endpoint. It distinguishes this tool from siblings like add_subscription_rate_plan and remove_subscription_rate_plan_charge by specifying it adds a charge, not a plan or other entity.

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 lists required fields and conditional requirements (e.g., when chargeType is recurring). However, it does not explicitly state when to use this tool versus alternatives like update or remove, nor does it provide exclusions or prerequisites beyond parameters.

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