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 two useful behavioral facts: it discloses the SOAP operation and warns that the numeric id comes from invoice replies rather than the printed invoice number. It doesn't describe what notes look like or whether there may be zero notes.

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 short sentences, front-loaded with what is returned and followed by the disambiguating identifier note. The trailing 'SOAP GetInvoiceNotes' is compact provenance with no wasted preamble.

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 one-parameter read tool with full schema coverage and complete safety annotations, the description covers what an agent needs to call it correctly. The only omission is the shape of the return value (ordering, whether notes include author or timestamp), which is minor without an output schema.

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 already 100%, with the single parameter documented as 'The invoice's InvoiceDBID'. The description goes beyond that by explaining where the id comes from and explicitly excluding the invoice number, which is the most likely source of a wrong call.

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: retrieves the notes attached to one sales invoice. It scopes to a single invoice and clarifies which identifier is required, so the agent can distinguish it from note-writing tools. It stops short of naming a sibling it might be confused with.

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 parenthetical clarifies which id to supply (InvoiceDBID, not the invoice number), which is an argument-selection hint rather than when-to-use guidance. It never says when to call this versus kashflow_get_invoice or kashflow_add_invoice_note, leaving the choice implicit.

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