cancel_subscription_purchase

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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It only states the primary action and omits critical details such as side effects (e.g., whether this stops renewals, triggers a refund), reversibility, permission requirements, or what the response contains. The tool is a mutation, so this is a significant gap.

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, grammatically correct sentence with no verbosity, but it is under-specified. It restates the tool's name without adding useful information, so while it is concise, it does not earn its place by providing unique 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?

For a tool with three parameters, a mutation, and a rich set of sibling tools, the description is severely lacking. It does not explain when to use it, what behavior changes based on cancellation_type, or how it differs from similarly named tools. The provided input schema and output schema help, but the description alone is insufficient for an agent to understand the tool's role.

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 the baseline is 3. The description adds no additional parameter semantics beyond what the schema already provides. The schema's parameter descriptions (e.g., cancellation_type values) are adequate, so a 3 is appropriate.

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 'Cancel a subscription purchase' clearly states the action (cancel) and the object (subscription purchase). It's specific and not a tautology, but it does not distinguish between sibling tools like revoke_subscription_purchase or defer_subscription_purchase, which could overlap in meaning.

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 provides no guidance on when to use this tool versus alternatives. There are no mentions of context, exclusions, or prerequisites, making it impossible for an agent to decide between cancel, revoke, or defer operations based on the description alone.

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