kashflow_get_invoiceOne sales invoice by its invoice number: customer, dates, lines (description, quantity, rate, VAT), net, VAT, amount paid and a link. SOAP GetInvoice.
| Name | Required | Description | Default |
|---|---|---|---|
| invoice_number | Yes | The invoice number, e.g. 1042. |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare read-only, non-destructive, open-world behavior, so the safety profile is covered. The description adds useful output context by listing the returned invoice fields and noting the SOAP method, but it does not mention error behavior such as what happens when the invoice number is not found.
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 compact and front-loads the core purpose, then efficiently enumerates the returned fields. The trailing 'SOAP GetInvoice' is slightly cryptic but does not bloat the definition.
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 simple one-parameter read tool with annotations and no output schema, the description gives enough detail about the returned invoice contents to support correct use. It could be more complete by stating not-found behavior or linking behavior, but the essential lookup context is present.
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%, and the single invoice_number parameter is documented with an example. The description only reinforces that the lookup is by invoice number, adding no syntax or format details beyond the schema.
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: retrieve one sales invoice by invoice number. It also names the returned fields and distinguishes this single-invoice lookup from the many sibling list-invoice tools.
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 phrase 'by its invoice number' implies the tool should be used when the invoice number is already known, but the description does not explicitly say when to use it instead of kashflow_list_invoices, kashflow_list_customer_invoices, or other invoice-related siblings. The usage context is only implied.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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