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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the returned field set, which is useful given there is no output schema, but says nothing about include_bank_transactions behavior or the difference between the two named API operations.

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?

Two compact clauses front-load the resource and field list, then the optional range. The trailing "Accounting.OutstandingCreditorItems / OutstandingCreditorItemsByDate" is cryptic endpoint jargon but does hint at two modes.

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 enumerated field list is exactly what the description needs to carry, and the pagination hints live in the schema. It falls short only on explaining the bank-transactions flag and the dual-operation naming.

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's list of returned fields and the date-range note add mild corroboration. It does not extend meaning for parameters like include_bank_transactions or sort_order, so it stays close to baseline.

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 resource (open items on the creditors list) clarified as unpaid purchase invoices, and enumerates the fields returned. That wording implicitly separates it from yuki_list_outstanding_debtor_items (sales invoices), but the sibling is never named.

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?

"Optionally within a date range" hints at when the date parameters apply, but there is no explicit guidance on when to choose this over the debtor-items sibling or how the two underlying operations are selected. Usage has to be inferred.

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