Metadata

Metadata is arbitrary structured data (string keys, JSON-serializable values) attached to traces. It helps you filter and understand production traffic in the Noryen UI.

Per-event metadata

Pass metadata on each track() call:

noryen.track({
  model: "gpt-4o-mini",
  prompt: "Hello",
  response: "Hi!",
  metadata: {
    userId: "usr_123",
    feature: "chat",
    deployment: "eu-west",
  },
});

Good candidates: internal user or tenant ids (non-PII where possible), feature flags, request route names, environment names, and correlation ids.

Global context with setContext

noryen.setContext(metadata) merges into a client-wide map. Every subsequent track() (including wrapper emissions) merges: global context first, then per-event metadata, so per-event keys override globals on conflict.

noryen.setContext({
  service: "billing-worker",
  version: process.env.APP_VERSION,
});

// Later events merge global context with per-event metadata
noryen.track({
  model: "gpt-4o-mini",
  prompt: "…",
  response: "…",
  metadata: { step: "invoice_summary" },
});
// Effective metadata includes service, version, and step

Wrapper-level metadata

When using wrappers, you can pass metadata in WrapOptions so every wrapped call includes the same fields:

const client = noryen.wrapOpenAI(openai, {
  metadata: { route: "api/chat" },
});