payping_send_invoiceSends a PayPing invoice to a customer by SMS or email after user confirmation.
Send an invoice to its customer by SMS/email from PayPing. Messages a real person: confirm with the user before calling.
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes |
Changes observed during successful MCP inspections.
v0.2.0Input schema / properties / code / titleRemoved value: -"Code"Input schema / titleRemoved value: -"payping_send_invoiceArguments"Output schema / (root)Previous value: -{
- "additionalProperties": true,
- "title": "payping_send_invoiceDictOutput",
- "type": "object"
-}New value: +nullv0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly=false, destructive=true, openWorld=true and idempotent=false, so the safety profile is covered. The description adds genuinely new context: the effect leaves the system as an outbound SMS/email to a human recipient, which explains the open-world/destructive hints and justifies the confirmation requirement.
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 tight sentences with zero filler: the action and channel first, then the operational caution. Nothing is repeated from the schema or annotations and nothing could be cut without losing information.
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 single-parameter mutation with no output schema, the description covers what happens and the key behavioral risk, and annotations cover idempotency and world-openness. The remaining gap is the meaning of the required 'code' argument, which is never clarified.
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?
One parameter ('code') with 0% schema description coverage, so the schema explains nothing and the description must compensate. The description only implies the code identifies the invoice; it never states the format, where the code comes from, or how to obtain it, leaving the sole required input under-specified.
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 (send) and resource (invoice) plus the delivery channels (SMS/email) and the service (PayPing). It is clearly distinguishable from reads like payping_get_invoice, though it never explicitly contrasts itself with payping_create_invoice, the nearest write sibling.
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?
Gives an explicit caution — 'Messages a real person: confirm with the user before calling' — which tells the agent this is a user-visible, irreversible-feeling action rather than a safe retrieval. It does not name alternative tools or state what to do if the invoice was already sent, so it stops short of full when/when-not guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.