update_line_item
Update a line item on an invoice. Find by index (0-based) or searchDescription. Can change description, quantity, rate, tax. Use this to fix mistakes instead of creating new invoices. Recalculates totals.
What update_line_item does
Updates an existing line item. Pass only the fields you want to change — every other field is preserved.
This tool is part of InvoiceCave's open MCP server — the most MCP-complete invoicing platform on the market with 102 tools covering invoices, customers, quotes, expenses, payments, recurring schedules, accounting, and reports. Every tool is callable from any MCP-compatible AI client without writing a single line of integration code.
How an AI uses update_line_item
Use this for partial edits — "change the due date to Net 30", "fix the customer's billing address", "update the line item description". The AI can read the current state with the matching get_* tool first if it needs to confirm what it's editing.
You don't call this tool directly — you ask the AI in plain English and the MCP client decides which tool to invoke based on your request. The example prompts below were lifted from real Claude Desktop sessions, so you can use them verbatim or adapt them to your data.
Parameters
update_line_item accepts 7 parameters — 1 required, 6 optional. The AI fills these in from your natural-language prompt; you never write them by hand.
| Parameter | Type | Required | Description |
|---|---|---|---|
| invoiceId | string | required | Invoice ID |
| lineItemIndex | number | optional | Line item index (0-based) |
| searchDescription | string | optional | Partial description text to find the line item |
| description | string | optional | New MULTI-LINE description. First line = bold title, \\n then sub-description. Example: "Web Design\\nClient: Acme" |
| quantity | number | optional | New quantity |
| rate | number | optional | New rate per unit |
| tax | number | optional | New tax percentage |
Request example
Under the hood, your AI client sends a JSON-RPC 2.0 tools/call request to InvoiceCave's MCP endpoint at https://www.invoicecave.com/api/mcp/mcp. Here's what a update_line_item call looks like:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "update_line_item",
"arguments": {
"invoiceId": "inv_a1b2c3d4",
"lineItemIndex": 100,
"searchDescription": "Acme",
"description": "Thanks for your business",
"quantity": 30
}
}
}You won't write this yourself — it's shown so developers can see exactly what the MCP client generates. The arguments object maps 1:1 to the parameters above. Authentication is handled by the Authorization: Bearer header with your API key.
Example AI prompts
Type any of these into Claude Desktop, Claude Code, or Cursor — InvoiceCave's MCP server will route them to update_line_item automatically.
“Update this line item — change the …”
“Fix the details on that line item.”
Use it in 30 seconds
Related tools
More from the Items & Catalog category.
list_itemsList products/services (items) in the organization. Optionally search by name.
create_itemCreate a new product or service item.
edit_itemUpdate an existing product or service item.
delete_itemDelete a product or service item.
add_line_itemAdd a new line item to an existing invoice. Automatically recalculates invoice totals. Description supports multi-line: first line = bold title, lines after \\n = sub-description.
remove_line_itemRemove a line item from an invoice by index (0-based) or by matching description text. Recalculates totals.
get_itemGet full details for a single product/service item by ID.
FAQ — update_line_item
What is update_line_item?▾
update_line_item is one of 102 tools in InvoiceCave's MCP server. Updates an existing line item. Pass only the fields you want to change — every other field is preserved. It's invoked automatically when an AI client like Claude or Cursor decides the user's request maps to this action.
Which AI clients can call update_line_item?▾
Any MCP-compatible client. We've tested it with Claude Desktop, Claude Code, Cursor, Windsurf, and Codex. The MCP protocol is open, so any AI tool that speaks MCP can call this endpoint with a valid InvoiceCave API key.
Is calling update_line_item secure?▾
Yes. Every call is authenticated by the API key you mint in the dashboard, scoped to a single organization, rate-limited per key, and recorded in the audit log with source='mcp'. Sensitive fields (SMTP passwords, encryption keys) are never returned to the AI client.
What parameters does update_line_item take?▾
update_line_item accepts 7 parameters — 1 required (invoiceId) and 6 optional. The AI populates these from your plain-English prompt — see the parameter table and request example above.
Does update_line_item count against any quota?▾
MCP tool calls are unmetered on the free plan up to a generous monthly limit. Once you connect Stripe and start charging your customers, every call still counts against the same per-key rate limit but doesn't add to your bill.
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