add_subscription_rate_plan_charge

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

With no annotations, the description discloses key behaviors: it is a POST (creating), notes required fields, highlights conditional requirements for billingPeriodAlignment/specificBillingPeriod when chargeType is recurring, and explains special handling of the weight parameter (multiplied by 100). Missing side effects or error conditions, but covers substantial behavioral details.

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 dense paragraph. It front-loads the purpose but becomes a run-on list of requirements. While efficient, it lacks structure (e.g., bullet points) and could be slightly more concise. Still, every sentence adds value.

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 17 parameters, no output schema, and complex constraints. The description thoroughly covers input requirements and conditional fields, but fails to mention return values, success/failure indicators, or error handling. This is a notable gap for a creation tool with no output schema.

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 100%, so baseline is 3. The description adds meaningful context beyond schema: grouping required fields, explaining the weight conversion, and clarifying the chargeTier array structure. This extra information helps the agent understand parameter usage beyond the schema descriptors.

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 provides the POST endpoint. It lists the purpose and required fields, but does not explicitly differentiate from sibling tools like `create_product_rate_plan_charge` which might be confused.

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 versus alternatives (e.g., `add_subscription_rate_plan` or `create_product_rate_plan_charge`). It does not state prerequisites or when not to use it, leaving the agent without decision support among many related tools.

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