Overview
Integrations overview
Connect Free Invoice Automation to your code, your store and your accounting tool. Every integration uses the same API, permissions and safety rules.
Free Invoice Automation is built API-first. The web app is only one way in: your own code, a command line, a Shopify store, a WordPress site, QuickBooks or Xero, and your AI assistant can all create and manage invoices. Every one of them calls the same API, with the same permissions, the same validation and the same audit trail, so no integration can do something the app would not allow.
All integrations are included on the Free plan. There is no extra charge for API access, connectors or accounting sync, and we never take a cut of your payments.
What is available and when
| Integration | What it does | Available |
|---|---|---|
| REST API | Every feature as an HTTP endpoint, with OpenAPI | At launch, 1 January 2027 |
| TypeScript SDK | A typed client generated from the OpenAPI document | At launch |
| Webhooks | Signed events sent to your URL when anything changes | At launch |
| MCP server | Use Claude, ChatGPT, Grok or Gemini to invoice | At launch |
| CLI | freeinvoiceautomation in your terminal and scripts | Week of 25 January 2027 |
| WordPress and WooCommerce | Invoices from WooCommerce orders, a pay-me block | Week of 25 January 2027 |
| Shopify | Invoices or receipts from Shopify orders | February 2027 |
| QuickBooks Online | One-way push of clients, items, invoices, credit notes and payments | May 2027 |
| Xero | The same one-way push into Xero | May 2027 |
| n8n | An n8n node for your workflows | Later, on demand |
At launch, the store connectors appear in Settings > Integrations with a "Coming soon" badge and a Notify me button, so you hear the day they ship.
How every integration works
One capability layer
Each action in the product, such as "create an invoice" or "record a payment", is defined once with its input, output, permission key and safety hints. The REST endpoint, the MCP tool, the CLI command, the SDK method and the connector actions are all generated from or call that one definition. If you learn one surface, the others behave the same way.
API keys with scopes
Integrations authenticate with an API key created in Settings > API keys. A key belongs to one account, carries scopes chosen from the permission keys, and can never do more than the person who created it can do right now. Store connectors get their own key for their install, limited to one business with only the scopes the connector needs (proposed). See Authentication.
Drafts first
Integrations and AI create drafts. A person confirms before anything is sent to a client, unless you deliberately turn on auto-send for a key, an AI automation, or a store install. Turning it on always needs a fresh sign-in. Destructive actions such as voiding or refunding always need explicit confirmation. See Drafts and confirmations.
Verified payments only
An invoice is marked paid only from a verified event: a signed webhook from Stripe, a verified store channel, a reconciliation run, or a person recording the payment. A browser redirect never marks anything paid. Shopify and WooCommerce payments count as verified only when they arrive through a signed channel, and are recorded with the source connector.
Everything is audited
Every write from every integration lands in the audit log with its actor: a user, an API key, an MCP client, the AI agent, a store connector, or the system. On Team you can view it under Audit log; on every plan it is recorded.
Choosing an integration
I want to create invoices from my own app or backend
Use the REST API directly, or the TypeScript SDK if you write TypeScript. Create a draft_only key, create drafts, and send them after a person approves; or create an auto_send key if your system should send by itself.
I want my systems to react when an invoice is paid
Add a webhook endpoint and subscribe to document.paid and payment.succeeded. See the event list.
I sell on Shopify or WooCommerce
Install the Shopify app or the WordPress plugin. Orders become invoices or receipts, numbered from your own sequence, and cancels and refunds are mirrored automatically.
My accountant uses QuickBooks or Xero
Connect QuickBooks Online or Xero. Clients, items, invoices, credit notes and payments are pushed one way into your books. We never read or change your ledger.
I script things in the terminal
Use the CLI. Every capability is a command, with the same permissions as your API key.
I work inside an AI assistant
Connect the MCP server to Claude, ChatGPT, Grok or Gemini. Your assistant does the AI work, so you need no AI credits for MCP.
Managing integrations in the app
Open Settings > Integrations to see what is connected: API keys, webhook endpoints, connected stores, and (from May 2027) QuickBooks or Xero. You need the integrations.manage permission for API keys, webhooks and store installs, and accounting.manage for accounting sync. Owners and Admins have both by default.
From there you can revoke a key, disable a webhook endpoint, unlink a store, or disconnect an accounting tool. Revoking or unlinking takes effect on the next request.
Security in short
- Keys are shown once and stored hashed. Revoke a key the moment you suspect it leaked.
- Webhook payloads are signed; verify every delivery.
- Store events are verified (Shopify's HMAC signature, or our signature on WordPress plugin calls) before anything is created.
- Accounting tokens are encrypted at rest and refreshed automatically.
- No card data ever reaches our servers.
See How we protect data for the full picture.