The flow
Starts it 2Model 1Logic 6Service 7
The steps in the order they run, from what starts it.
- 1On Workflow ErrorError triggerStarts it
- 2Schedule – Poll Milestones1Schedule triggerStarts it
- 3Slack – Send Error AlertSlackService
- 4Sheets – Read Milestones1Google SheetsService
- 5Filter – Ready to Invoice1CodeLogic
- 6IF – Skip if None Ready1IfLogic
- 7Code – Calculate Billable Amount1CodeLogic
- 8GPT-4o – Write Invoice Narrative1Open AiModel
- 9Code – Merge GPT + Build Approval URL1CodeLogic
- 10Code – Generate HTML Invoice1CodeLogic
- 11Gmail – Send Invoice to Client1GmailService
- 12If1IfLogic
- 13Sheets – Mark Invoice as Sent1Google SheetsService
- 14Sheets – Log Invoice1Google SheetsService
- 15Sheets – Update Approval Status1Google SheetsService
- 16Slack – Notify Accounts Team1SlackService
How it's built
- Starts on
- A clock
- Steps
- 16, with 2 branches
- Size
- Medium: a working afternoon
- Connects to
- Gmail, Google Sheets, Slack
- Model
- OpenAI
Questions
What does it need to run?
An n8n account, plus your own Gmail, Google Sheets and Slack accounts, and a key for OpenAI. You connect your own accounts after importing it; none are included.
What starts it?
It starts on a clock.
Does it use AI?
Yes. It calls OpenAI. Model calls are billed by the provider, not by n8n.
How long does it take to set up?
Plan an afternoon. 16 steps is enough that you should read each one before running it.
How do I import it?
Copy the workflow, open a new workflow in n8n and paste. The steps appear on the canvas, ready for your own accounts.
Nothing here has been tested by us. It is somebody's working automation, read and described from its own steps. Treat the connections it wants as a list of accounts it will touch, and read the 16 steps before you point it at anything that matters.