Costs - Muster

Ingest cost event

POST /api/v1/costs/events

No authentication required. Cost events are created automatically when you include token_input, token_output, and model in your quality signal POST. Body:

{
  "agent_id": "invoice-processor-v2",
  "job_id": "job-001",
  "model": "gpt-4o",
  "provider": "openai",
  "input_tokens": 1247,
  "output_tokens": 312
}

Response:

{
  "event_id": "uuid",
  "cost_usd": 0.0343,
  "cost_display": 0.03,
  "display_currency": "USD"
}

Cost summary

GET /api/v1/costs/summary?days=30

{
  "period_days": 30,
  "total_cost_usd": 5481.89,
  "total_cost_display": 5481.89,
  "unattributed_cost_usd": 0,
  "display_currency": "USD",
  "daily_trend": [
    {
      "date": "2026-02-22",
      "cost_usd": 190.54,
      "cost_display": 190.54
    }
  ]
}

Agent cost detail

GET /api/v1/costs/agents/{agent_id}?days=30

Department costs

GET /api/v1/costs/departments

Returns this month’s spend grouped by department, with budget utilisation if budgets are set.

Set department budget

POST /api/v1/costs/budgets

{
  "department": "Finance",
  "month": "2026-03-01",
  "budget_amount": 5000.00
}

​Ingest cost event

​Cost summary

​Agent cost detail

​Department costs

​Set department budget

Ingest cost event

Cost summary

Agent cost detail

Department costs

Set department budget