update_invoice

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

With no annotations, the description carries the full burden, and it does disclose the single most consequential behavioral rule: editability is gated on invoice state, with posted invoices reduced to status and memo changes. It omits what actually happens when a disallowed field is submitted (silent drop vs. error), whether changes are reversible, and any auth requirements, so the disclosure is important but incomplete.

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 sentences, zero filler, and the resource identification is front-loaded ahead of the state-dependent constraint. Every clause earns its place.

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?

For a mutation tool with no annotations, no output schema, and a nested payload, the description covers the critical state gate but leaves gaps: no statement of what the response returns, how rejected field edits are surfaced, or whether status changes require specific permissions. Adequate, but not complete for a write operation of this complexity.

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 50% and the nested `invoice` object carries no top-level description, so the schema only partly documents the payload. The description compensates by tying specific fields (status, memo) to the posted-invoice restriction, but it never addresses dueDate, termsCode, or which status transitions are actually permitted, so it adds partial rather than full meaning.

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 states a specific verb and resource ('Update an existing invoice in KikoBooks'), which is unambiguous and clearly distinct from create_invoice/get_invoice/search_invoices. It stops short of naming any sibling tool explicitly, so an agent must infer the boundaries itself, but the purpose itself is unmistakable.

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 gives conditional guidance tied to the invoice's state: full edit for DRAFT, limited edit (status and memo only) for posted invoices. That is genuinely useful when-to-use context, though it never names sibling alternatives (e.g., void_bill for voiding instead of status-editing) or states prerequisites such as required permissions.

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