The InvoiceBadger MCP server

InvoiceBadger has two front doors onto the same data: a plain web app, and a remote MCP server. The MCP server lets the AI assistant you already have open create clients, log time, raise invoices and tell you who has not paid, without you leaving what you were doing.

Connecting it

The server is remote and hosted, so there is nothing to install and no API key to paste.

• Add https://invoicebadger.com/mcp as a connector in your MCP client.
• Sign in with your InvoiceBadger email and password when the consent page appears. That is the OAuth flow; your client receives a token scoped to your account.
• Restart your client. Most MCP clients only load a server's tools when a session starts, so a newly connected server looks broken until you do. This catches almost everyone once.

Transport is streamable HTTP. The server is also published to the Official MCP Registry as com.invoicebadger/invoice-badger.

Tools

Fourteen tools, covering the whole invoicing loop.

Clients

• add_client creates a client with an hourly rate, email and address.
• update_client changes any of those. Fields you leave out keep their current value.
• list_clients lists your clients and their rates.

Invoices

• new_invoice opens a draft invoice for a client.
• log_time adds hours to a draft, billed at that client's rate unless you say otherwise.
• add_item adds a fixed fee line.
• invoice_status shows one invoice with its lines and total.
• list_invoices lists invoices, optionally filtered by status.
• delete_invoice removes a draft. Sent and paid invoices stay for the record.

Getting paid

• mark_sent, mark_paid and mark_draft move an invoice through its states. Only drafts accept new lines, so set an invoice back to draft if you need to correct it.
• invoice_pdf returns a link to the PDF, ready to attach to an email.
• outstanding totals everything unpaid.

Example prompts

• Add Acme Ltd as a client at 60 an hour.
• Log 90 minutes on the Acme invoice for the API fixes.
• What is still unpaid?
• Mark Acme's March invoice paid.

Authentication and access

Every request to /mcp sits behind OAuth. Without a valid token you get a 401 and no tool runs. The token carries your account id, and every tool scopes its queries to that account, so a valid token for one account cannot reach another's data. Discovery is standard, at /.well-known/oauth-authorization-server and /.well-known/oauth-protected-resource.

Write operations are capped per account per day. That is an abuse backstop rather than a plan limit.

What it costs

Nothing. The MCP server is on the free plan, which also includes unlimited invoices and clients. Pro adds your own logo, the full set of invoice themes and removes the badge from invoices you send.

Questions or something not working? Email support@invoicebadger.com.