Connect Invoiced to Claude: Manage Invoices, Payments & Subscriptions

If you need to connect Invoiced to Claude to automate accounts receivable, trigger metered billing invoices, or resolve customer payment disputes, you need a Model Context Protocol (MCP) server. This server acts as the translation layer between Claude's natural language tool calls and the Invoiced REST API. You can either construct and host this infrastructure yourself, or use a managed integration platform like Truto to dynamically generate a secure, authenticated MCP server URL. If your team uses ChatGPT, check out our guide on /connect-invoiced-to-chatgpt-automate-billing-and-customer-accounts/ or explore our broader architectural overview on /connect-invoiced-to-ai-agents-streamline-ar-and-collection-tasks/.

Giving a Large Language Model (LLM) read and write access to a billing engine like Invoiced is an architectural challenge. You have to handle token lifecycles, map massive JSON schemas to MCP tool definitions, and deal with Invoiced's strict payment gateway tokenization rules. Every time Invoiced updates an endpoint or changes a subscription parameter, you have to update your server code, redeploy, and test the integration.

This guide breaks down exactly how to use Truto to generate a secure, managed MCP server for Invoiced, connect it natively to Claude Desktop, and execute complex billing workflows using natural language.

The Engineering Reality of the Invoiced API

A custom MCP server is a self-hosted integration layer. While the open MCP standard provides a predictable way for models to discover tools, the reality of implementing it against specialized financial APIs is painful. Invoiced is built to handle complex accounts receivable flows, and its API reflects that strictness.

If you decide to build a custom Invoiced MCP server, here are the specific integration challenges you will face:

Asynchronous Billing States (Sweeping) Unlike simpler invoicing tools where you just create an invoice and attach line items, Invoiced uses a metered billing concept called "Pending Line Items." These are unbilled charges attached to a customer. To bill them, you cannot just update their status. You must call a specific trigger endpoint (invoiced_pending_line_items_trigger_invoice) that sweeps all pending items into a new consolidated invoice. An LLM cannot intuit this state-machine logic. A managed MCP server exposes these exact state transitions as distinct, documented tools.

Strict Payment Source Tokenization When processing a charge via the Invoiced API, you cannot just pass arbitrary payment data. The API strictly requires exactly one of three mutually exclusive authentication methods: payment_source_type combined with payment_source_id, an invoiced_token, or a gateway_token. If an LLM attempts to pass more than one, or misformats the payload, the request fails. Truto's MCP tools derive their JSON schemas directly from curated API documentation, strictly defining the required properties and enforcing the correct flat input namespace before the request ever reaches the proxy execution layer.

Raw Rate Limit Passthrough Financial APIs enforce strict concurrency limits. It is a critical factual note that Truto does not retry, throttle, or apply backoff on rate limit errors. When the upstream Invoiced API returns an HTTP 429, Truto passes that error directly to the caller. Truto normalizes upstream rate limit info into standardized headers (ratelimit-limit, ratelimit-remaining, ratelimit-reset) per the IETF spec. The caller (your agent or framework) is strictly responsible for implementing retry and backoff logic. Do not build an MCP server expecting it to magically absorb API quotas.

Step 1: Create the Invoiced MCP Server

Truto's MCP architecture turns any connected integration into a JSON-RPC 2.0 endpoint. Tool generation is dynamic and documentation-driven. Rather than hand-coding tool definitions, Truto derives them from the integration's resource endpoints and schema definitions.

You can create an MCP server for Invoiced using either the Truto UI or the Truto API.

Method A: Via the Truto UI

1. Navigate to the Integrated Accounts page in your Truto dashboard and select your connected Invoiced account.
2. Click the MCP Servers tab.
3. Click Create MCP Server.
4. Select your desired configuration (e.g., restrict to read methods only, or filter by specific tags like billing).
5. Copy the generated MCP server URL. (You will only see the raw token once).

Method B: Via the API

You can dynamically provision an MCP server for a specific tenant by hitting the Truto API. This validates that the integration is AI-ready, hashes the secure token for edge key-value storage, and returns the URL.

curl -X POST https://api.truto.one/integrated-account/{integrated_account_id}/mcp \
  -H "Authorization: Bearer YOUR_TRUTO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Invoiced Billing Agent",
    "config": {
      "methods": ["read", "write", "custom"]
    }
  }'

Response:

{
  "id": "mcp_srv_9x8y7z",
  "name": "Invoiced Billing Agent",
  "config": {
    "methods": ["read", "write", "custom"]
  },
  "expires_at": null,
  "url": "https://api.truto.one/mcp/a1b2c3d4e5f6..."
}

Step 2: Connect the MCP Server to Claude

Once you have the Truto MCP URL, you need to register it with Claude. You can do this visually in the UI or manually via a configuration file.

Method A: Via the Claude UI

1. Open Claude Desktop or the web interface.
2. Navigate to Settings -> Integrations -> Add MCP Server (or Settings -> Connectors -> Add depending on your plan tier).
3. Paste your Truto MCP URL into the Server URL field.
4. Give it a name (e.g., "Invoiced Integration") and click Add.

Claude will immediately perform the protocol handshake and discover all available Invoiced tools.

Method B: Via Manual Config File

For Claude Desktop developers, you can edit your local claude_desktop_config.json file. Because Truto provides a remote SSE (Server-Sent Events) endpoint, you will use the official @modelcontextprotocol/server-sse transport wrapper.

Add the following to your configuration file:

{
  "mcpServers": {
    "invoiced": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-sse",
        "https://api.truto.one/mcp/a1b2c3d4e5f6..."
      ]
    }
  }
}

Restart Claude Desktop. The agent will initialize the connection, verifying the cryptographic token stored at the edge, and load the schemas.

Hero Tools for Invoiced

When Claude connects to the Truto MCP server, it gains access to the Invoiced API operations converted into discrete, schema-validated tools. Here are the highest-leverage tools available for AI billing agents.

invoiced_customers_get_balance

Retrieves a customer's current credit balance, balance history, and total amount outstanding. This is the foundational tool for AR health checks and dispute resolution, returning a comprehensive snapshot without needing to aggregate invoices manually.

"Check the current balance and outstanding past-due amounts for the customer with ID 9812. If they have available credits, let me know."

create_a_invoiced_pending_line_item

Creates a pending line item for metered billing. This charge is parked on the customer's account and will be automatically swept into their next triggered invoice. Ideal for usage-based SaaS billing automation.

"Log a pending line item for customer 5510 for 'Overage API calls'. The quantity is 4500 and the unit cost is $0.02. Mark it as taxable."

invoiced_pending_line_items_trigger_invoice

Forces Invoiced to consolidate all of a customer's open pending line items into a single, brand new invoice. This acts as the state transition from 'unbilled usage' to 'active receivable'.

"Trigger an invoice for customer 5510 to sweep all of their pending usage charges for this month into a final bill."

create_a_invoiced_payment

Creates a payment representing a cash receipt or credit balance application. It uses the applied_to array to allocate the payment across specific invoices or estimates.

"Record a manual wire transfer payment of $5,000 for customer 4099, and apply the full amount to invoice ID 10443."

invoiced_invoices_send_email

Sends a specific invoice to a customer via email. It can optionally use custom templates and subjects, making it perfect for automated dunning agents.

"Send a reminder email for invoice 10443 using the 'Overdue Notice' template. Send it to the primary billing contact."

create_a_invoiced_subscription

Creates a recurring subscription billing schedule for a customer, applying a specific plan, optional addons, and tax rules. This automates the start of a recurring revenue contract.

"Create a new subscription for customer 8821 using the 'Enterprise Annual' plan starting today. Do not apply any discounts."

To view the complete inventory of available Invoiced tools, including query parameters, body schemas, and required fields, visit the Invoiced integration page.

Workflows in Action

Connecting Claude to Invoiced via MCP transforms complex multi-step financial operations into simple conversational commands.

Scenario 1: End-of-Month Metered Billing Sweep

SaaS companies often log usage dynamically and bill at the end of the month. Instead of writing custom cron jobs, an AI agent can orchestrate the billing sweep.

"Log 50 hours of 'Premium Support' at $150/hr as a pending charge for Acme Corp (ID 1099). Once logged, trigger their end-of-month invoice and email it to them."

sequenceDiagram
    participant User as User
    participant Claude as Claude Desktop
    participant MCP as Truto MCP Server
    participant Invoiced as Invoiced API
    
    User->>Claude: "Log 50 hours support, trigger invoice, send email"
    Claude->>MCP: Call create_a_invoiced_pending_line_item(customer: 1099, qty: 50)
    MCP->>Invoiced: POST /customers/1099/line_items
    Invoiced-->>MCP: Returns pending item ID
    MCP-->>Claude: Success response
    Claude->>MCP: Call invoiced_pending_line_items_trigger_invoice(customer: 1099)
    MCP->>Invoiced: POST /customers/1099/invoices
    Invoiced-->>MCP: Returns Invoice ID 4002
    MCP-->>Claude: Success, Invoice 4002 created
    Claude->>MCP: Call invoiced_invoices_send_email(invoice_id: 4002)
    MCP->>Invoiced: POST /invoices/4002/emails
    Invoiced-->>MCP: Returns email delivery status
    MCP-->>Claude: Success
    Claude-->>User: "Logged 50 hours, generated Invoice #4002, and emailed to customer."

1. Claude identifies the need to create a metered charge and calls create_a_invoiced_pending_line_item with the quantity and rate.
2. Recognizing that pending items must be swept, Claude calls invoiced_pending_line_items_trigger_invoice to generate the actual invoice object.
3. Claude parses the new Invoice ID from the response and passes it into invoiced_invoices_send_email to distribute the bill.

Scenario 2: AR Health Check and Payment Application

When a large wire transfer hits the bank, accounts receivable teams must check outstanding balances and manually apply the cash to specific invoices.

"Check the outstanding balance for Globex (ID 302). If they owe money, log a $10,000 wire transfer payment and apply it to their oldest open invoice."

sequenceDiagram
    participant User as User
    participant Claude as Claude Desktop
    participant MCP as Truto MCP Server
    participant Invoiced as Invoiced API
    
    User->>Claude: "Check balance Globex, apply $10k wire to oldest invoice"
    Claude->>MCP: Call invoiced_customers_get_balance(customer_id: 302)
    MCP->>Invoiced: GET /customers/302/balance
    Invoiced-->>MCP: Returns balance: $14,000, past_due: $10,000
    MCP-->>Claude: Returns balance payload
    Claude->>MCP: Call list_all_invoiced_invoices(customer: 302, sort: date asc)
    MCP->>Invoiced: GET /invoices?customer=302
    Invoiced-->>MCP: Returns Invoice ID 8812
    MCP-->>Claude: Returns open invoices
    Claude->>MCP: Call create_a_invoiced_payment(amount: 10000, applied_to: [{invoice: 8812}])
    MCP->>Invoiced: POST /payments
    Invoiced-->>MCP: Returns Payment ID
    MCP-->>Claude: Success
    Claude-->>User: "Globex owed $14,000. I applied the $10,000 wire to Invoice 8812."

1. Claude calls invoiced_customers_get_balance to verify the customer owes money.
2. Claude fetches open invoices via list_all_invoiced_invoices to identify the oldest receivable.
3. Claude executes create_a_invoiced_payment, carefully formatting the applied_to array to allocate the funds exactly against the target invoice.

Security and Access Control

Giving AI models write access to a financial system of record requires strict security boundaries. Truto's MCP architecture enforces constraints at the server level, meaning the LLM cannot override them.

• Method Filtering: Limit a server strictly to non-destructive actions. Setting methods: ["read"] ensures the agent can query balances and view invoices, but cannot issue refunds or delete customers.
• Tag Filtering: Group tools by functional area. You can restrict an MCP server to only expose tools tagged with subscriptions or payments, isolating the agent's capabilities.
• Require API Token Auth: By default, possession of the MCP URL grants access. By setting require_api_token_auth: true, the caller must also provide a valid Truto API token in the Authorization header - adding a second layer of identity verification.
• Expiration Scheduling: Create temporary access grants. By setting an expires_at timestamp, the edge key-value storage and resilient scheduling primitives will automatically purge the server and revoke access at the exact deadline.

The Strategic Move to Managed MCP

Building an integration with Invoiced is not just about making a single POST request - it requires managing API versions, strict token logic, nested schemas, and asynchronous state changes. If you build a custom MCP server, you own the maintenance burden of tracking the Invoiced API lifecycle forever.

By using Truto to generate a managed MCP server, you offload the infrastructure. Truto handles the schema derivation, protocol routing, and edge authentication, giving Claude a standardized, normalized interface to execute billing workflows on day one. Your engineers get to focus on prompting the agent, while Truto handles the underlying financial API execution.