Configuration Reference

Every `init()` option, in both SDKs, with defaults.

Python	TypeScript	Default	Notes
`subscription_key`	`subscriptionKey`	—	Required. From Settings → Tracing.
`base_url`	`baseUrl`	hosted ingest	Trace ingest endpoint; override for self-hosting.
`api_url`	`apiUrl`	hosted control-plane	Scenario generation / control-plane endpoint.
`service_name`	`serviceName`	`"unknown"`	Service label shown on every span in the dashboard.
`environment`	`environment`	`None`	`development` \\| `staging` \\| `production`.
`app_version`	`appVersion`	`None`	e.g. `"1.2.3"` — shown alongside spans.
`device_id`	`deviceId`	`None`	Stable client/device id, for per-device APM analytics.
`debug`	`debug`	`false`	Logs span exports to stdout.
`max_export_batch_size`	`maxExportBatchSize`	`512`	Spans per export batch.
`scheduled_delay_ms`	`scheduledDelayMillis`	`5000`	Export interval, in ms.
`max_queue_size`	—	`4096`	Python only — max buffered spans before drop.
`max_body_bytes`	`maxBodyBytes`	10 MB	Max captured HTTP/LLM body size per span.
`function_tracing`	—	`true`	Python only — auto-trace your app’s own functions on import. Also via env `EVALKIT_FUNCTION_TRACE=false`.
`trace_packages`	—	`None`	Python only — extra package names to auto-trace beyond the caller’s directory (e.g. sibling packages).

Self-hosting the ingest/control-plane services yourself? Point base_url/baseUrl at your trace-service and api_url/apiUrl at your orchestrator — everything else about the SDK is unchanged.