Update Invoice Settings

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

Annotations already declare idempotentHint=true and destructiveHint=false, so the description does not need to reiterate those. The description adds the partial-update behavior hint ('Pass only the fields to change'), but does not disclose other behaviors like authorization requirements, rate limits, or return value shape. Since annotations cover safety, a 3 is appropriate.

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?

The description is a single sentence that conveys the purpose and usage guideline efficiently. Every word adds value—no fluff, no repetition. It is front-loaded with the action and resource, then specifies the scope and modification pattern.

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?

While the description covers core purpose and usage, it omits information about the return value (e.g., whether it returns the updated settings or a success message). Given the lack of an output schema, this is a gap. Also, the behavior when no fields are passed (all optional) is not addressed. The description is minimally complete for a simple update tool but could be more helpful.

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% with individual parameter descriptions. The description adds semantic grouping by categorizing fields (contact details, template, email text, footer), which helps an agent understand the logical groups. It also reinforces the partial-update pattern. This adds value beyond the schema, justifying a 4.

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 clearly states the tool updates company invoice settings, listing specific categories (contact details, default template, email text, footer). This distinguishes it from sibling tools like get_invoice_info (read) and update_invoice_series (series-specific). The verb-resource combination is precise and unambiguous.

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 provides a clear usage guideline ('Pass only the fields to change'), indicating partial updates are supported. It implicitly suggests when to use this tool (to modify global invoice settings) but does not explicitly exclude alternatives or provide when-not-to-use scenarios, which would elevate it to a 5.

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