Lucius API
Usage

Submit usage events

Submit up to 100 usage events in a single request. Each event is validated against the contract's pricing program, persisted, rated immediately, and the corresponding invoice is updated. Events are idempotent — submitting the same `event_id` twice returns success without creating a duplicate.

POST
/v1/billing/usage
AuthorizationBearer <token>

API key as Bearer token: Authorization: Bearer luc_live_...

In: header

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

curl -X POST "https://api.lucius.finance/v1/billing/usage" \  -H "Content-Type: application/json" \  -d '{    "events": [      {        "external_contract_id": "acme-corp-2026",        "event_id": "evt-2026-03-001",        "metric": "revenue_amount_invoiced",        "quantity": 10000,        "timestamp": "2026-03-25T12:00:00.000Z"      }    ]  }'
{
  "accepted": 1,
  "rejected": 0,
  "events": [
    {
      "event_id": "evt-2026-03-001",
      "status": "accepted"
    }
  ]
}

{
  "error": "Missing API key"
}