Middleware Telemetry Safety

Operator wants every call to enforce maxTokens<=2000 regardless of caller. They mutate the params arg in-place inside transformParams.

Middleware transformParams({params}) must return a new params object (immutable transform). Returning undefined or mutating in place leads to inconsistent provider state across concurrent calls. Use `return { ...params, maxTokens: Math.min(params.maxTokens ?? 2000, 2000) }`.

Operator expects per-call traces in Vercel Observability but the dashboard is empty — no `experimental_telemetry` option was set.

experimental_telemetry is opt-in. Pass `experimental_telemetry: { isEnabled: true, functionId: 'chat-route', metadata: { userId } }` on each generate*/stream* call. Configure an OTEL SDK at boot (Vercel sets one up automatically when @vercel/otel is present).

Operator enables experimental_telemetry with default `recordInputs:true, recordOutputs:true` — chat transcripts including PHI ship to a third-party observability vendor.

Default to `recordInputs:false, recordOutputs:false` for any tenant where transcripts may contain PII/PHI. Span attributes still capture model id, usage, latency, errors without prompt text. If you must record, route to a compliance-vetted exporter and verify with the vendor's BAA/DPA scope.