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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states 'This tool never books,' clearly signaling a read-only, non-destructive operation. It also mentions the default date behavior, which is a behavioral detail. However, it doesn't discuss potential side effects, rate limits, or error handling, but for a simple getter this is sufficient context.

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 concise and well-structured. It opens with the core purpose, then provides parameter-specific guidance, and ends with a clear behavioral note. Each sentence adds value without redundancy. The front-loading of the main action and the use of short, clear sentences make 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's simplicity (3 parameters, no nested objects, no output schema), the description covers the essential information: purpose, parameter usage, and a key behavioral trait (non-booking). It does not describe the return format, but the tool name implies it returns available slots. For a straightforward read operation, this is adequate, though a note about the response shape would improve completeness.

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 has zero description coverage, so the description must explain the parameters. It explains 'booking_page' thoroughly (page or widget URL), explains 'date_iso' usage ('Omit date_iso for today'), and hints at a filter ('Optionally filter by part of an appointment type name'). However, it does not explicitly map this filter to the 'room' parameter, leaving ambiguity about which parameter is used for filtering. The description adds meaning beyond the schema but is not fully explicit about all parameter roles.

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 tool's function: 'Get public OnlineAfspraken slots for a booking page and ISO date.' It specifies the resource (public slots), the action (get), and the required context (booking page and date). It also mentions an optional filter, giving a complete picture of the tool's purpose. Since there are no sibling tools, no differentiation is needed, but the description is unambiguous.

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 concrete usage instructions: how to specify the booking_page (page embedding a widget or the widget URL itself), how to handle the date ('Omit date_iso for today in Europe/Amsterdam'), and the optional filter by appointment type name. It also explicitly states 'This tool never books,' which is a clear exclusion that guides the agent on when not to use it (for booking actions). While it doesn't list alternatives, the absence of siblings makes this acceptable.

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