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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=true), so the bar is lower. The description adds genuinely useful behavior beyond that: pagination cap of 100 per page, how cursor/next_cursor round-trips, and that an API key with app access is required.

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?

Reasonably front-loaded, but there is clear redundancy: 'oldest due date first' and 'Sorted by due date, oldest first' say the same thing, and days_overdue is introduced then re-explained. Trimming these repeats would sharpen it without losing information.

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?

There is no output schema, and the description compensates by naming the returned fields (days_overdue, total_outstanding) and the pagination contract. Combined with the auth note, it is complete enough for correct invocation, though edge cases like zero-result behavior are unaddressed.

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 limit, cursor, customer, and min_days_overdue; baseline is 3. The description restates the cursor round-trip and days_overdue semantics but adds no syntax, format, or default detail beyond what the schema provides.

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 and resource (list overdue invoices) and precisely defines the subset returned — invoices past due date with a remaining balance. An agent can distinguish this from erpnext_list_sales_invoices without opening either schema, since the overdue filter is spelled out.

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 clearly delimits when this tool applies by defining 'Overdue' as past due date with a balance remaining, which implicitly routes the agent here for collections work. However, it never names the sibling alternative (e.g. list_sales_invoices) or states when-not to use it, so it falls short of explicit routing.

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