Get rental status

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

With no annotations provided, the description carries the burden of describing behavior. It clearly states what information is returned (status, phone number, and SMS messages received so far), and the phrase 'so far' implies a point-in-time snapshot. While it could mention error handling or side effects, this is a read-only operation and the description is sufficiently transparent for its simple nature.

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 that directly states what the tool does. Every word adds value, with no fluff or repetition. It is appropriately sized for the tool's simplicity.

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 get operation with one parameter and no output schema, the description gives a solid overview of the return contents (status, phone number, SMS messages). It does not detail the status values or message structure, but given the tool's limited scope and the presence of sibling tools, it provides enough context for an agent to use it effectively.

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's description for rentalId is clear and meaningful ('The rentalId returned by rent_number'), so schema coverage is 100%. The tool description itself does not add further parameter detail, but the schema already provides the necessary context, meeting the baseline for high coverage.

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 uses the specific verb 'Check' and clearly identifies the resource: a rental's status, phone number, and SMS messages. This distinguishes it from sibling tools like list_services (which lists services) and rent_number (which rents a number), so the agent knows exactly what this tool does.

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 the tool is used to retrieve current information about a rental, and the parameter description (in the schema) notes the ID comes from rent_number. This gives clear context for when to call it, though it does not explicitly compare it to alternatives like wait_for_sms. Still, the purpose is clear enough to guide correct selection.

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