invoice_issued_overdue_days

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 clearly discloses that the tool performs local date arithmetic and has no external side effects, which is valuable transparency. It does not mention edge cases like future due dates or timezone handling, but for a simple date-difference calculation this is adequate.

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 two short sentences with no filler. The core purpose is front-loaded, and the important behavioral trait ('does not contact AbraFlexi') is placed in the second sentence where it reinforces rather than obscures the purpose.

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 low complexity, a single documented parameter, and an existing output schema, the description covers everything needed to invoke it correctly. It states the input, the computation, and the lack of external side effects, so no critical context is missing.

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 baseline is 3. The description only says 'given its due date' and adds no additional meaning beyond the schema's ISO 'YYYY-MM-DD' string description. The schema already carries the parameter semantics.

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 starts with a specific verb and resource: 'Get the number of days an invoice is overdue by, given its due date.' It clearly identifies the output (overdue days) and the input (due date), and the 'pure date arithmetic' clause distinguishes it from sibling tools that interact with the AbraFlexi API.

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 gives useful context by stating this is pure date arithmetic and does not contact AbraFlexi, which implies it is appropriate for offline or quick calculations. However, it does not explicitly state when to prefer this tool over alternatives or when not to use it, leaving the usage guidance mostly implied.

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