curl --request GET \
  --url https://studio.eigenpal.com/api/v1/runs/{id}/usage \
  --header 'Authorization: Bearer <token>'

{
  "usage": {
    "tokens": {
      "input": 123,
      "output": 123,
      "cacheRead": 123,
      "cacheWrite": 123
    },
    "creditsCharged": 123,
    "durationMs": 123,
    "llmCallCount": 123,
    "ocrPagesProcessed": 123,
    "agentTurns": 123
  }
}