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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description goes further by disclosing the return envelope ({ results, count, has_more, next_cursor }) and that each invoice embeds line items, totals, amount paid/due and transactions — useful context given there is no output schema.

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?

Three tight sentences: what it lists, how it can be filtered, and what comes back, ending with the endpoint. No filler and the core purpose is front-loaded.

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 a 9-parameter, zero-required, fully documented schema and read-only annotations, the remaining burden is the response shape, which the description supplies since no output schema exists. Pagination is also addressed via next_cursor. Only the absence of explicit sibling routing keeps it from being 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% and every parameter is documented in the schema, including the enum values, defaults and cursor semantics. The description restates the same filters (status, customer, territory, creation time) without adding format or constraint detail beyond the schema, so the baseline 3 applies.

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 (List) and resource (invoices) plus the full filter surface (status, customer, territory, creation time). It is clearly distinct from the singular get_invoice sibling by the plural listing semantics, but it never names an alternative explicitly, so differentiation is implicit rather than stated.

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?

Usage is implied by the filter list — an agent can infer this is the bulk/query tool versus get_invoice for a single record — but there is no explicit when-to-use or when-not-to-use guidance, and no mention of the related list_transactions tool for invoice transactions.

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