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

Annotations already cover the read-only, open-world, non-destructive profile, and the description adds real behavioral context on top: default sort order ('newest posting date first'), the 100-per-page cap, cursor mechanics, and an auth requirement (Cotlet API key with app access). It does not describe response shape or error behavior, but that gap is minor.

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?

Front-loaded with the resource and returned fields, then filters, then pagination and auth. Six compact sentences with little waste, though the status/outstanding definitions could be trimmed for an agent that only needs to call it.

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 no output schema, the description correctly carries the return-value burden by naming the fields, and it also covers pagination, auth, and filtering. Only the sibling-routing and response-shape details are absent.

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%, so the six parameters are already documented; baseline is 3. The description adds semantic color for status and outstanding amount, but it refers to 'next_cursor' while the schema field is named 'cursor', which could mildly confuse the paging mapping.

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 uses a clear verb+resource ('Lists Sales Invoice records') and names the fields returned (status, due date, total, outstanding). It does not, however, distinguish itself from close siblings like erpnext_list_overdue_invoices or erpnext_get_sales_invoice, which share the same resource.

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?

It states the available filters (status, customer, posting date range), which implies usage, but never says when to prefer this tool over erpnext_list_overdue_invoices or erpnext_get_sales_invoice, and gives no exclusions or preconditions.

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