pup_list_non_school_days

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

The readOnlyHint annotation already communicates that this is a safe read operation. The description adds meaningful behavioral details about what date categories are included and the optional 'differs from defaults' behavior. However, it does not clarify output structure, ordering, whether the optional result is additive, or what happens if only one of start_date or end_date is supplied.

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 sentence with no filler. It front-loads the core purpose and then states the optional behavior, 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?

The tool is simple and the annotations provide read-only safety, but there is no output schema and the description leaves some operational details unclear, such as the exact relationship between the non-school-day list and the 'differs from defaults' list, and how the date range parameters interact. It is adequate for basic use but not fully complete.

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 parameters are already documented well in structured form. The description reinforces the range/diff behavior but does not add significant semantic detail beyond what the schema already provides for individual parameters.

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 identifies the tool's function as listing dates when a plan cannot be set at a school, with explicit categories such as holidays, closures, and weekends. It also mentions the optional behavior related to student defaults. It does not explicitly compare against sibling tools, but the resource and verb are specific enough to distinguish it.

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 intended use is implied: use this tool when determining dates a plan cannot be scheduled. The optional start/end date behavior is mentioned, but there is no explicit guidance on when to use this tool versus related siblings like pup_list_plans or pup_get_default_plans, nor are any exclusions stated.

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