list_rentals

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

With no annotations provided, the description carries the behavioral disclosure burden. It explicitly states 'Read-only,' which is a key safety trait, and clarifies that 'active' means 'what's running and billing.' This adds meaningful context beyond the bare schema, though it does not mention pagination or return format, which are common for list tools.

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 extremely concise: four short sentences that front-load the purpose, then efficiently cover defaults and the read-only nature. Every sentence contributes value without repetition, making it easy for an agent to parse quickly.

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?

Given the tool has only one optional parameter, no output schema, and no annotations, the description covers all essential aspects: purpose, default behavior, parameter usage, and safety. It does not describe return values or pagination, but for a simple list operation this is a minor omission, and the description is otherwise complete enough 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 input schema already defines the status parameter with an enum and default, but the description adds semantic meaning by explaining that the default includes only active rentals and that 'all' gives full history. This directly clarifies what each value represents, going beyond the schema's generic description.

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 begins with 'List the account's rentals,' which uses a specific verb and resource, clearly distinguishing it from siblings like get_rental (single rental) and create_rental/destroy_rental. The scope ('account's rentals') and default behavior ('active ones') further clarify its purpose.

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 clear usage context: by default only active rentals are returned, and passing status='all' retrieves full history. It does not explicitly mention alternatives, but the sibling names make the appropriate tool obvious, and the guidance on the status parameter is practically sufficient.

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