Invoicey

Invoicey connects your workspace to ChatGPT. Describe the work, review the invoice in an interactive card, and decide when to issue or send it. The same invoice stays available in Invoicey.

Start here

The customer page, available in Czech and English, previews the planned public connection flow. Public installation is not available yet: the app needs review and publication in ChatGPT. Customers will open the listing and connect their own Invoicey account.

The instructions below are for developers and invited testers with custom-app access. The private development plugin link is not a public invitation.

Developer and invited-tester setup

Create an Invoicey workspace and add a default issuer, contact email, VAT settings and bank account.
On ChatGPT web, enable Developer mode if your account offers it. Open Plugins → Add → Create MCP App (some accounts use Apps → Create). Organization users may need an administrator.
Name the app Invoicey, enter https://invoicey.app/api/mcp, and choose OAuth. Use automatic client registration when offered; do not paste personal API keys into chat.
Connect, sign in to Invoicey, select the workspace and approve access. Return to ChatGPT.
Start a new conversation, select the connected Invoicey app, and ask: “Show my recent invoices in Invoicey.” This first check only reads data.

If custom-app creation is unavailable, this early-access setup is not supported by your account. A public directory release will provide the simpler install path after review and publication. See OpenAI's custom-app access guidance.

Two Invoicey entries during early testing

Invoicey is the connected app with live tools. Invoicey workflows is an optional skill package (version 1.0.3). You do not need that package for the setup above. Its package version is separate from the app listing's version. If a chat says tools are unavailable, start a new chat and select the connected app directly. Do not disconnect the working app to remove the optional workflow package.

Desktop, web and mobile

The live ChatGPT integration has been verified for invoice listing and interactive draft creation. The consent flow has desktop and mobile-browser regression coverage. Complete initial setup on ChatGPT web. Custom-app access on phones depends on ChatGPT's current host support; native iOS/Android behavior has not yet been validated. Composer invoice mentions are host-dependent. A responsive view alone does not establish native mobile availability.

From a sentence to an invoice

Prepare a draft for 12 hours of design at 1,500 CZK per hour. Use my workspace seller, look up the client's confirmed IČO, and ask me for any missing details. Show me the draft before issuing it.

Invoicey validates client details, dates, currency, document language and line items. The assistant should ask for missing facts instead of inventing them. Review the recipient, amounts, VAT, due date and assumptions. Ask for a correction or confirm issuance when ready.

The invoice view lets you:

Search invoices by client or number and filter unpaid invoices.
Review seller, recipient, items, taxes and totals.
Issue a saved draft, send an invoice to a chosen email address, or record payment after confirmation.
Open stored PDF and ISDOC documents or continue in the Invoicey web app.
Attach an invoice to the current conversation without sending a new message.

In supporting hosts, type @ and search Invoicey invoices to attach a reference. Only invoices in the connected workspace are available. Issued invoices cannot be changed through the draft editor.

Workspace and access

OAuth access stays bound to the workspace you approved, even if you switch workspaces in the Invoicey website. Connect again to approve a different workspace. Permissions are checked on every request: removing a member or changing their role changes what the connection can do.

To disconnect, open Workspace settings → Integrations → ChatGPT & MCP in Invoicey and remove the application's connection. Remove it in ChatGPT as well if you no longer want it listed. Signing out/revoking the originating Invoicey session also invalidates that connection.

Troubleshooting

Sign-in repeats: reconnect and approve access again. Do not paste API keys into the conversation.
No issuer: add a default issuer in Invoicey before asking for a draft.
Missing action: check your workspace role, plan and approved write access.
No interactive card: your host may support tools only. The assistant can still use the MCP tools; open Invoicey to inspect the document.
Wrong workspace: reconnect and select the intended workspace on the consent screen.

Historical invoice import, recurring schedules and bank connection setup remain in the web app. See MCP for other assistants and personal-key clients.

ChatGPT