set_subscription_contract_next_billing_date

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

No annotations are provided, so the description carries the full burden. It only says 'set' without disclosing side effects, whether the contract must be active, whether changes are reversible, or how billing schedules are affected. This is a significant lack of behavioral transparency for a mutation tool.

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, front-loaded sentence with no wasted words. It is concise and immediately communicates the core action and target resource.

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 operation is simple and both parameters are fully documented, making the invocation clear. However, the lack of behavioral context (e.g., contract state requirements, side effects, what happens to prior billing date) leaves the description minimally acceptable but not complete for a mutation tool without annotations or 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?

The input schema covers both parameters with clear descriptions (ISO 8601 format for date, contract ID). The description adds no extra parameter meaning, but the baseline of 3 applies because schema description coverage is 100%.

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 'Set the next billing date for a subscription contract' uses a specific verb and resource, making the action unambiguous. It clearly distinguishes this from sibling subscription contract operations like cancel, pause, or activate.

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 implies usage when the next billing date needs to be changed, but it does not explicitly state when to use this tool versus alternatives or provide exclusions. Among many subscription contract sibling tools, no when-not-to-use guidance is given.

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