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

With no annotations provided, the description carries the burden of behavioral disclosure. It reveals a key constraint (only 'watching' state backorders can be cancelled) and the effect (stops watching a domain), but it doesn't describe error behavior for invalid states, reversibility, or any side effects beyond stopping the watch.

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 two short, front-loaded sentences with no filler. The core action and the state constraint are presented clearly and efficiently, earning every word its place.

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 simple one-parameter cancel operation, the description covers the essential purpose and constraint, making it reasonably complete. It omits error handling and postcondition details, but given the simple scope and lack of an output schema, it provides enough context for an agent to select and invoke the tool correctly.

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 schema already documents the only parameter ('id') fully, and the description adds no further semantic detail. Since schema coverage is 100%, the baseline of 3 is appropriate, as the description doesn't need to compensate for missing parameter information.

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 ('cancelling a backorder') and the purpose ('Stop watching a domain'), using a specific verb and resource. It also differentiates from sibling cancel tools like cancel_broker_request and cancel_plan by focusing on backorders and the 'watching' state.

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 gives clear context on when to use this tool: when you want to stop watching a domain via a backorder, and it explicitly notes that only backorders in the 'watching' state are eligible. It doesn't name alternative tools, but the precondition provides actionable usage guidance.

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