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

The description claims 'Writes nothing and creates nothing,' but the annotations declare readOnlyHint=false, meaning the tool is explicitly not marked as read-only. That is a direct contradiction. No other behavioral details such as return shape, validation, errors, or auth requirements are added.

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 main content is compact and front-loaded, stating purpose and side-effect guarantee in two sentences. The trailing 'Pro.' is unnecessary and slightly detracts, but overall the description is not padded.

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?

This is a transformation/payload-builder with no output schema and no return-format explanation; an agent is left to guess what the generated items look like. The undefined 'MAJOR units'/'MINOR units' and the lack of any example or output shape make the description incomplete for a non-trivial tool.

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?

With 100% schema description coverage, the baseline is 3; the description adds little to the parameter semantics. It mentions VAT at the shared profile rate, aligning with tax_rate's override semantics already documented in the schema, but it does not elaborate on issue_date or change_order identification.

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 names a specific verb ('Build'), a specific resource ('the approved delta'), and the prepared output types ('invoice_create-ready items ... quote_create-ready items'), which clearly differentiates it from change_order_get, change_order_document, and the mutation siblings. The title reinforces that it produces a payload rather than performing a domain action.

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 context is implied by 'approved delta' and the 'invoice_create-ready'/'quote_create-ready' wording, suggesting it is called before creating invoices/quotes from an approved change order. However, there is no explicit when-to-use, when-not-to-use, or naming of alternatives, so guidance is inferred rather than stated.

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