Add notes about OTLP ingestion limitations

Author: gggritso

docs/concepts/otlp/index.mdx

@@ -7,7 +7,11 @@ keywords: ["otlp", "otel", "opentelemetry"]
 
 <Include name="feature-available-for-user-group-limited-avail.mdx" />
 
-Sentry can ingest [OpenTelemetry](https://opentelemetry.io) traces directly via the  [OpenTelemetry Protocol](https://opentelemetry.io/docs/specs/otel/protocol/). If you have an existing OpenTelemetry trace instrumentation, you can configure your OpenTelemetry exporter to send traces to Sentry directly.
+Sentry can ingest [OpenTelemetry](https://opentelemetry.io) traces directly via the  [OpenTelemetry Protocol](https://opentelemetry.io/docs/specs/otel/protocol/). If you have an existing OpenTelemetry trace instrumentation, you can configure your OpenTelemetry exporter to send traces to Sentry directly. Sentry's OTLP ingestion endpoint is currently in development, and has a few known limitations:
+
+- Span events are not supported. All span events are dropped during ingestion.
+- Span links are partially supported. We ingest and display span links, but they cannot be searched, filtered, or aggregated. Links are are shown in the [Trace View](https://docs.sentry.io/concepts/key-terms/tracing/trace-view/).
+- Array attributes are partially supported. We ingest and display array attributes, but they cannot be searched, filtered, or aggregated. Array attributes are shown in the [Trace View](https://docs.sentry.io/concepts/key-terms/tracing/trace-view/).
 
 The easiest way to configure an OpenTelemetry exporter is with environment variables. You'll need to configure the trace endpoint URL, as well as the authentication headers. Set these variables on the server where your application is running.