update_subscription_contract_product

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action and does not reveal side effects, whether it triggers proration, what happens if both optional parameters are provided or neither, permission requirements, or the nature of any returned data. This is a mutation tool and requires more behavioral context.

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 sentence with no irrelevant details. It is appropriately concise and the core message is communicated clearly without wasted words.

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?

For a mutation tool with no annotations and no output schema, the description is insufficiently complete. It does not clarify whether the operation updates a specific line item, what the expected response is, or the conditions under which the optional parameters should be used. The lack of context relative to the sibling subscription contract tools makes this hard for an agent to invoke 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 100% with each parameter documented. The tool description adds no additional meaning about how parameters interact, such as whether at least one of the optional parameters must be supplied or how they combine. Baseline 3 is appropriate since the schema fully documents individual parameters but the description does not enrich the semantics.

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 a specific action: 'Change a product or product price in a subscription contract.' It identifies the verb (change), the resource (product/product price within a subscription contract), and distinguishes this from sibling tools such as cancel, pause, or activate subscription contracts.

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 its use for updating an existing subscription contract line, but it does not provide explicit guidance on when to use it versus alternatives, nor does it mention any prerequisites or exclusions. The intended usage is inferred from the name and description rather than explicitly stated.

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