npm / @vercel/otel

@vercel/otel

What changed in @vercel/otel 1 to 2, from its official release notes, upgrade guides and advisories. Sources checked 2026-11-11.

12 breaking8 new APIs and options3 behavior and defaults4 fixes and other

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@vercel/otel 226 changes

Inbound baggage headers are limited to 180 entries and 8,192 bytes, and entries larger than 4,096 bytes are skipped.
2.2.0release notes
When trace drains are used, auto-configuration based on OTEL_EXPORTER_OTLP_ environment variables is ignored to avoid duplicate trace export.
1.14.0, 2.1.0release notes release notes
The minimum supported Node.js version is now ^18.19.0 || >=20.6.0; Node.js 14 and 16 are no longer supported.
2.0.0release notes
The compatible version range is now >=1.9.0 <3.0.0, raised from >=1.7.0 <2.0.0.
2.0.0release notes
The compatible version range is now >=0.200.0 <0.300.0, raised from >=0.46.0 <0.200.0.
2.0.0release notes
The compatible version range is now >=0.200.0 <0.300.0, raised from >=0.46.0 <0.200.0.
2.0.0release notes
The compatible version range is now >=2.0.0 <3.0.0, raised from >=1.19.0 <2.0.0.
2.0.0release notes
The compatible version range is now >=0.200.0 <0.300.0, raised from >=0.46.0 <0.200.0.
2.0.0release notes
The compatible version range is now >=2.0.0 <3.0.0, raised from >=1.19.0 <2.0.0.
2.0.0release notes
The compatible version range is now >=2.0.0 <3.0.0, raised from >=1.19.0 <2.0.0.
2.0.0release notes
Replace the single logRecordProcessor option with logRecordProcessors, an array of processors.
2.0.0release notes
Replace the single metricReader option with metricReaders, an array of readers.
2.0.0release notes

When this environment variable is set and no OTLP endpoint is configured, the 'auto' exporter sends traces over the Unix socket.
2.3.0release notes
Processors in spanProcessors now receive onEnding, allowing span attributes to be changed or removed before any exporter sends the span, including the 'auto' exporters.
2.2.1release notes
Configure the OTLP export timeout in milliseconds.
2.2.0release notes
Configure the OTLP trace export timeout in milliseconds.
2.2.0release notes
Set the export request timeout in milliseconds; requests now abort after 10 seconds by default.
2.2.0release notes
Set how long the span flush queued in waitUntil waits before giving up; the default is 10 seconds on Vercel.
2.2.0release notes
Vercel defaults now emit the OpenTelemetry resource attribute cloud.provider with the value vercel.
2.1.3release notes
@vercel/otel adds support for OpenTelemetry JS SDK 2.x.
2.0.0release notes

OTLP JSON exports now include a flags field on each span and link; sampled spans send 257, or 769 when the parent is remote. http/protobuf exports are unchanged.
2.2.1release notes
Set the export request timeout in milliseconds; requests now abort after 10 seconds by default.
2.2.0release notes
Adds standard OpenTelemetry resource attributes for VCS.
1.14.1, 2.1.2release notes release notes

An export that fails before sending reports the failure right away instead of stalling for 30 seconds.
2.2.0release notes
Prevents duplicate spans when code running before registerOTel replaces get with a function that calls the exported request.
2.1.4release notes
System environment variables are no longer inlined.
2.1.1release notes

Avoids local OTLP exports for drained Vercel traces when request context is lost before span end.
1.14.2release notes