Parent evening

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

"Read-only; nothing is booked" adds real value beyond the annotations: in a parent-evening domain an agent might reasonably assume slot booking, and this explicitly forecloses it. The annotations already cover readOnly/destructive/idempotent, so the description is correctly focused on the non-obvious consequence rather than restating them.

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?

Three short sentences, front-loaded with the resource and its contents, then the id-omission rule, then the safety note. Nothing is padding; every clause carries information an agent needs.

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?

With one optional parameter, full schema coverage, rich annotations, and no output schema, the description covers both lookup modes and the no-side-effect guarantee. It doesn't hint at what the response shape looks like in the message-search case, which is the only remaining gap.

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?

Schema coverage is 100% and the single id parameter is already documented in the schema with the same omit-to-search behavior. The description restates that behavior without adding format or example detail, so it hits the baseline rather than exceeding it.

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?

It names a specific resource (parent evening / ouderavond) and enumerates what it exposes: invitation, time slots and chosen teachers. It's clear enough that an agent can tell it apart from the sibling list, since no other sibling covers parent evenings, though the verb is implied rather than stated ("details").

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?

"Without id, finds invitations linked in your messages" gives an explicit routing rule between the two invocation modes, with the schema-backed id path as the alternative. It stops short of naming other tools or stating when not to call it, but the mode selection is unambiguous.

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