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

Annotations already indicate a non-read-only, idempotent, non-destructive mutation. The description adds useful context about the observable effects: stopping future outreach and canceling unsent messages. However, it does not clarify edge cases such as whether canceled messages remain visible or whether the customer can be resubscribed later.

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 substantive sentence is short and front-loaded, but the trailing 'Unsubscribe Customer' wording in the description duplicates the title and adds no value. Still, the core content is concise and easy to parse.

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 one integer parameter, full schema coverage, an output schema, and informative annotations, the description covers the essential behavior. It is incomplete only in that it does not disambiguate from the closely related cancelCustomerUnsentMessages sibling.

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%, and the only parameter 'id' is already documented as the unique numeric identifier for the customer. The description adds no additional parameter-level meaning, so the baseline of 3 applies.

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 gives a specific verb and resource: 'Unsubscribe a customer from future outreach and cancel unsent messages.' This clearly states what the tool does, though it overlaps with the sibling cancelCustomerUnsentMessages because it also mentions canceling unsent messages.

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 is provided about when to use this tool versus alternatives such as cancelCustomerUnsentMessages or resubscribeCustomer. The description does not state when not to use it or name any fallback options.

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