list_departments

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the description need not restate safety. It adds useful behavioral context: the result includes the VVZ path needed for course listing, and the set is described as 'all top-level units' plus 'special categories', which clarifies the open-world 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, well-structured sentence that front-loads the core purpose and adds necessary detail about what is included. No wasted words.

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 (one optional parameter, no nested objects, output schema present), the description is nearly complete. It could explicitly mention that the output is a list of department names with paths, but the output schema likely covers that.

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 description coverage is 100%, so the schema already documents the semester parameter fully, including examples and defaults. The description adds no additional parameter semantics, which is acceptable given the schema's completeness.

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 states a specific verb ('list') and resource ('top-level units of the Vorlesungsverzeichnis'), and clarifies what those units are (SPL departments plus special categories) and what each entry includes (the VVZ path needed to list its courses). This distinguishes it from sibling tools like search_units or get_unit.

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 when to use this tool: to get top-level departments and their VVZ paths before listing courses. It does not explicitly name alternatives or exclusions, but the context of siblings and the clear scope provide adequate guidance.

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