whmcs_add_paymentRecord an invoice payment by providing invoice ID, amount, gateway, and transaction ID. Accepts optional date, fees, and email suppression.
Record a payment on an invoice
| Name | Required | Description | Default |
|---|---|---|---|
| date | No | Payment date (YYYY-MM-DD) | |
| fees | No | Transaction fees | |
| amount | No | Payment amount | |
| gateway | Yes | Payment gateway name | |
| noemail | No | Do not send email | |
| transid | Yes | Transaction ID | |
| invoiceid | Yes | Invoice ID |
Changes observed during successful MCP inspections.
v1.2.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden but only states the action. It does not disclose side effects (e.g., invoice status changes), permissions, or idempotency, leaving significant behavioral gaps.
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 only one sentence, which is under-specified for a tool with 7 parameters. While concise, it sacrifices important detail, making it less useful.
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?
Given no output schema and 7 parameters, the description lacks essential context such as return values, invoice status effects, or prerequisites, resulting in incomplete guidance.
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%, so baseline is 3. The description adds no parameter-specific meaning beyond the schema, offering minimal added value.
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 'Record a payment on an invoice' clearly states the verb (record) and the resource (payment on an invoice), distinguishing it from siblings like whmcs_apply_credit or whmcs_create_invoice.
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 description provides no guidance on when to use this tool vs alternatives, such as whether to use it when an invoice is open or how it relates to other payment actions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.