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

Annotations already cover the safety profile (readOnly, idempotent, not open-world), and the description adds real context beyond them: the restaurant only operates Fri/Sat/Sun, and the response conveys both open status and free-table count. It does not mention auth, rate limits, or closed-day edge cases, but for a trivial read that is minor.

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?

One dense sentence that front-loads the resource (weekend restaurant), the day-scope constraint, and the return semantics with zero filler. Nothing is wasted and nothing important is buried.

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 one-parameter read tool with an output schema, the description tells the agent what it gets back (open/closed plus table count) and the Fri/Sat/Sun constraint that governs validity. Only the sibling-routing guidance is missing, which is a small gap for this complexity level.

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?

Single parameter with 100% schema coverage, including the YYYY-MM-DD pattern and description, so the schema does the heavy lifting. The phrase 'op een datum' adds nothing beyond the schema's format spec; baseline 3 is appropriate.

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?

States a specific verb (controleer) and resource (restaurant open status + free tables) plus a scoping constraint (weekendrestaurant, vr/za/zo). It clearly differentiates from getCamperAvailability and getAccommodationDetails by domain, but never names an alternative tool explicitly.

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?

Usage is implied: call it with a date to learn whether the weekend restaurant is open and how many tables are free. There is no statement of when not to use it or which sibling to prefer for other availability domains, so the agent must infer routing from the names alone.

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