Send an invoice to a contact by email, generating the PDF and Stripe payment link and delivering both in one action.
Send an invoice to the contact via email. Generates PDF, creates Stripe payment link, and sends via email.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Invoice UUID — must be draft, pending, sent, or overdue |
Changes observed during successful MCP inspections.
v4.71.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden and does well by disclosing three real side effects: PDF generation, Stripe payment-link creation, and outbound email. It does not say whether the invoice status changes, whether sending is idempotent/repeatable, or what permissions are required — gaps for an irreversible outbound-send tool.
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, no filler, with the primary action front-loaded and the side effects following as supporting detail. 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?
There is no output schema and no annotations, so the description should ideally describe what comes back (e.g. updated invoice or the generated link) and failure conditions. It explains the process but not the result, leaving the agent unable to anticipate the response shape.
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 schema already documents the single 'id' parameter including the allowed statuses. The description adds no parameter-level detail (no format, no constraints, no behavior tied to the id), so the baseline 3 applies.
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?
States a specific verb and resource ('Send an invoice') and immediately names the concrete side-effect chain (PDF generation, Stripe payment link, email delivery). This clearly separates it from siblings like get_invoice, create_invoice, or update_invoice, which do not deliver anything.
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 is only implied: an agent can infer this is the delivery step for an existing invoice. There is no explicit statement of when to prefer it over e.g. update_invoice or a generic send_email call, and no note on prerequisites such as the invoice needing a contact with a valid email address.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.