Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@simple_invoicing-mcp List all unpaid invoices"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
MCP (Model Context Protocol) server that acts as a bridge to any deployed simple_invoicing FastAPI instance.
This server exposes the simple_invoicing REST API as MCP tools, making it usable directly from Claude Desktop, Cursor, or any other MCP-compatible client.
Node.js ≥ 18
A running simple_invoicing FastAPI backend
A long-lived bearer token (API token) for the backend
Related MCP server: mcp-buchhaltungsbutler
git clone https://github.com/nikhilb2/simple_invoicing-mcp.git
cd simple_invoicing-mcp
npm install
npm run buildSet these environment variables before running:
export INVOICING_BASE_URL=https://your-invoicing-instance.example.com
export INVOICING_API_TOKEN=your-long-lived-bearer-token-hereOr copy .env.example to .env and fill in the values.
Open your simple_invoicing backend's Swagger UI (usually at /docs)
Use the /api/auth/login endpoint with your credentials
Copy the access_token from the response
Use this token as INVOICING_API_TOKEN
npm run devThis starts the MCP server on stdio using tsx.
Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):
{
"mcpServers": {
"invoicing": {
"command": "node",
"args": ["/absolute/path/to/simple_invoicing-mcp/dist/index.js"],
"env": {
"INVOICING_BASE_URL": "https://invoicing.example.com",
"INVOICING_API_TOKEN": "your-token-here"
}
}
}
}Add to .cursor/mcp.json in your project root:
{
"mcpServers": {
"invoicing": {
"command": "node",
"args": ["/absolute/path/to/simple_invoicing-mcp/dist/index.js"],
"env": {
"INVOICING_BASE_URL": "https://invoicing.example.com",
"INVOICING_API_TOKEN": "your-token-here"
}
}
}
}Tool | Description | Parameters |
| List all invoices with optional filtering |
|
| Get a single invoice by ID |
|
| Create a new invoice |
|
| Get the PDF for an invoice |
|
Tool | Description | Parameters |
| List all products |
|
| Get a single product by ID |
|
| Create a new product |
|
Tool | Description | Parameters |
| List all ledgers |
|
| Get the statement for a ledger |
|
| Get the day book entries |
|
Tool | Description | Parameters |
| List all inventory items |
|
Tool | Description | Parameters |
| List all buyers |
|
| Get a single buyer by ID |
|
Tool | Description | Parameters |
| List all payments |
|
| Create a new payment |
|
npm install # Install dependencies (set NODE_ENV=development for devDeps)
npm run build # Compile TypeScript
npm test # Run testsMIT
Create a new invoice
Inputs: data (required).
Create a new payment
Inputs: data (required).
Create a new product
Inputs: data (required).
Get a single buyer by ID
Inputs: id (required).
Get the day book entries with optional date range
Inputs: start_date, end_date.
Get a single invoice by ID
Inputs: id (required).
Get the PDF for an invoice (returns base64 if available)
Inputs: id (required).
Get the statement for a ledger with optional date range
Inputs: id (required), start_date, end_date.
Get a single product by ID
Inputs: id (required).
List all buyers
Inputs: skip, limit.
List all inventory items
Inputs: skip, limit.
List all invoices with optional filtering
Inputs: invoice_type, skip, limit.
List all ledgers
Inputs: skip, limit.
List all payments
Inputs: skip, limit.
List all products
Inputs: skip, limit.
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
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Scored across 15 tools
Each tool targets a distinct resource (invoice, payment, product, buyer, ledger, inventory) with unique operations (create, get, list). No two tools have overlapping purposes, making it easy for an agent to select the correct one.
All tool names follow a consistent verb_noun pattern (e.g., create_invoice, get_buyer, list_invoices) using lowercase snake_case. No mixing of conventions or vague verbs like 'process' or 'do_thing'.
With 15 tools, the surface is well-scoped for a simple invoicing system covering core entities (invoices, payments, products, buyers, ledgers, inventory). Each tool earns its place without unnecessary bloat or deficiency.
The tool set provides basic CRUD operations (create and read/list) for most entities but lacks update and delete functionalities (e.g., update_invoice, delete_product). While the core workflow of creating and reading is covered, agents may hit dead ends when needing to modify or remove records.
Create and manage invoices and customers on Jupiter Invoice (MCP, API-key auth).
Host any HTTP API as MCP tools with a tamper-evident cross-agent settlement ledger.
Free hosted MCP for invoices, estimates, clients, items and PDFs. OAuth authorization required.
Invoice Simple MCP server for ChatGPT, Claude and any AI agent: create invoice, send invoice, create estimate, list unpaid invoices and mark invoice paid in your own Invoice Simple account. Cotlet works in the account through your Cloud Browser, a real Chrome where you sign in to Invoice Simple yourself; Cotlet does not store your password and you need no Invoice Simple API key. About the official Invoice Simple API: Invoice Simple publishes no public API, API keys or developer documentation; its plans offer built-in payment integrations instead (checked 8 Nov 2026). It has no official MCP server. Setup and FAQ: https://cotlet.dev/integrations/invoice-simple-api-mcp-server
