`invoices.create`

Create a draft invoice for a customer. By default it starts from the customer's last invoice (lines, currency, notes, payment methods, terms); pass startFrom blank to start empty. Totals and sales tax are calculated on the server. Pass projectId to tie it to a project.

POST/api/v1/accounting/invoices.create

Permissions

accounting:readaccounting:write

Who can call it

admin, finance

Retries

Idempotency key required

MCP

accounting_invoices_create

Fields

partyIdstring (ID)Required
The ID of a customer or vendor account, from parties.list.
startFromenum
lastblank
Default "last"
titlestring
A short title.
at most 200 characters
issueDatestring or null
The date the document was issued, as YYYY-MM-DD.
dueDatestring or null
The date payment is due, as YYYY-MM-DD.
currencystring
Three-letter currency code, such as CAD or USD.
linesarray of objects
at most 100 items
taxTreatmentenum or null
autohstgstgst_qstzero_ratedexemptnonecustom
taxRateCodeenum or string or null
paymentMethodIdsarray of strings (ID)
A list of record IDs.
at most 10 items
payUrlstring (uri) or null
notesstring
Notes kept with the record.
at most 4000 characters
memostring
at most 4000 characters
termsobject
No other fields
billToContactIdstring or null
projectIdstring (ID) or null
idempotencyKeystringRequired
Any unique text you generate once per intended change, so a retried request only happens once. Send it as the Idempotency-Key header instead if you prefer; if you send both they must match.
8–200 characters

curl https://app.getoatmilk.com/api/v1/accounting/invoices.create \
  -H "Authorization: Bearer $OATMILK_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10"
}'

const response = await fetch("https://app.getoatmilk.com/api/v1/accounting/invoices.create", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OATMILK_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": crypto.randomUUID(),
  },
  body: JSON.stringify({
    "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10"
  }),
});
const { data, error } = await response.json();
if (!response.ok) throw new Error(`${error.code}: ${error.message}`);
console.log(data);

import os
import uuid

import requests

response = requests.post(
    "https://app.getoatmilk.com/api/v1/accounting/invoices.create",
    headers={
        "Authorization": f"Bearer {os.environ['OATMILK_API_KEY']}",
        "Idempotency-Key": str(uuid.uuid4()),
    },
    json={
        "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10",
    },
    timeout=30,
)
payload = response.json()
if not response.ok:
    raise RuntimeError(f"{payload['error']['code']}: {payload['error']['message']}")
print(payload["data"])

Response

{
  "data": { … }
}

Try it

Checks your input with this action’s real schema and answers like the API, with synthetic data. No key needed, and nothing changes.

Input

POST/api/v1/accounting/invoices.create

curl https://app.getoatmilk.com/api/v1/accounting/invoices.create \
  -H "Authorization: Bearer $OATMILK_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10"
}'

const response = await fetch("https://app.getoatmilk.com/api/v1/accounting/invoices.create", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OATMILK_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": crypto.randomUUID(),
  },
  body: JSON.stringify({
    "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10"
  }),
});
const { data, error } = await response.json();
if (!response.ok) throw new Error(`${error.code}: ${error.message}`);
console.log(data);

import os
import uuid

import requests

response = requests.post(
    "https://app.getoatmilk.com/api/v1/accounting/invoices.create",
    headers={
        "Authorization": f"Bearer {os.environ['OATMILK_API_KEY']}",
        "Idempotency-Key": str(uuid.uuid4()),
    },
    json={
        "partyId": "7f0f6c1e-1c1f-4b5e-9c8d-2f5e8e3c1a10",
    },
    timeout=30,
)
payload = response.json()
if not response.ok:
    raise RuntimeError(f"{payload['error']['code']}: {payload['error']['message']}")
print(payload["data"])

Fields

Fields inside lines

Fields inside terms

Example

Try it