`invoices.groups.groupSelected`

Group 2 to 100 selected existing invoices as one split bill. Give the project, group name, currency and each invoice id with expectedRevision. Atomically creates a group and ties every selected invoice to that project. Invoices may belong to different businesses but must share the chosen currency and have no existing billing group. Stale invoices or an unavailable project refuse the whole change. Amounts, tax, recipients, payments, numbers, sending schedules and status stay as saved. Returns the saved group; inspect it with invoices.groups.get.

POST/api/v1/accounting/invoices.groups.groupSelected

Permissions

accounting:readaccounting:write

Who can call it

admin, finance

Retries

Idempotency key required

MCP

accounting_invoices_groups_group_selected

Fields

projectIdstring (ID)Required
The ID of the related record.
namestringRequired
A display name.
1–200 characters
currencystringRequired
Three-letter currency code, such as CAD or USD.
invoicesarray of objectsRequired
2–100 items
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.groups.groupSelected \
  -H "Authorization: Bearer $OATMILK_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
  "name": "Synthetic Ventures Inc.",
  "currency": "CAD",
  "invoices": [
    {
      "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
      "expectedRevision": 3
    },
    {
      "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
      "expectedRevision": 3
    }
  ]
}'

const response = await fetch("https://app.getoatmilk.com/api/v1/accounting/invoices.groups.groupSelected", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OATMILK_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": crypto.randomUUID(),
  },
  body: JSON.stringify({
    "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
    "name": "Synthetic Ventures Inc.",
    "currency": "CAD",
    "invoices": [
      {
        "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
        "expectedRevision": 3
      },
      {
        "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
        "expectedRevision": 3
      }
    ]
  }),
});
const { data, error } = await response.json();
if (!response.ok) throw new Error(`${error.code}: ${error.message}`);
console.log(data);

import os
import uuid

import requests

response = requests.post(
    "https://app.getoatmilk.com/api/v1/accounting/invoices.groups.groupSelected",
    headers={
        "Authorization": f"Bearer {os.environ['OATMILK_API_KEY']}",
        "Idempotency-Key": str(uuid.uuid4()),
    },
    json={
        "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
        "name": "Synthetic Ventures Inc.",
        "currency": "CAD",
        "invoices": [
            {
                "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
                "expectedRevision": 3,
            },
            {
                "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
                "expectedRevision": 3,
            },
        ],
    },
    timeout=30,
)
payload = response.json()
if not response.ok:
    raise RuntimeError(f"{payload['error']['code']}: {payload['error']['message']}")
print(payload["data"])

Response

{
  "data": { … }
}

This action checks your data too, so replace the example values with your own before sending it.

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.groups.groupSelected

curl https://app.getoatmilk.com/api/v1/accounting/invoices.groups.groupSelected \
  -H "Authorization: Bearer $OATMILK_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
  "name": "Synthetic Ventures Inc.",
  "currency": "CAD",
  "invoices": [
    {
      "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
      "expectedRevision": 3
    },
    {
      "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
      "expectedRevision": 3
    }
  ]
}'

const response = await fetch("https://app.getoatmilk.com/api/v1/accounting/invoices.groups.groupSelected", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OATMILK_API_KEY}`,
    "Content-Type": "application/json",
    "Idempotency-Key": crypto.randomUUID(),
  },
  body: JSON.stringify({
    "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
    "name": "Synthetic Ventures Inc.",
    "currency": "CAD",
    "invoices": [
      {
        "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
        "expectedRevision": 3
      },
      {
        "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
        "expectedRevision": 3
      }
    ]
  }),
});
const { data, error } = await response.json();
if (!response.ok) throw new Error(`${error.code}: ${error.message}`);
console.log(data);

import os
import uuid

import requests

response = requests.post(
    "https://app.getoatmilk.com/api/v1/accounting/invoices.groups.groupSelected",
    headers={
        "Authorization": f"Bearer {os.environ['OATMILK_API_KEY']}",
        "Idempotency-Key": str(uuid.uuid4()),
    },
    json={
        "projectId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
        "name": "Synthetic Ventures Inc.",
        "currency": "CAD",
        "invoices": [
            {
                "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
                "expectedRevision": 3,
            },
            {
                "id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d",
                "expectedRevision": 3,
            },
        ],
    },
    timeout=30,
)
payload = response.json()
if not response.ok:
    raise RuntimeError(f"{payload['error']['code']}: {payload['error']['message']}")
print(payload["data"])

Fields

Fields inside invoices

Example

Try it