2026.4.1
nextauthjs/next-auth2026.4.1Apr 24, 2026by GabrielBianconi
AI Summary
Major release introducing TypeScript evaluators, vLLM reasoning support, and observability enhancements, with a breaking change regarding async writes.
Key Highlights
- Added TypeScript evaluators for inference evaluations
- Added support for vLLM's new reasoning field
- Added aggregated variant usage data to the UI
- Added inference cost data to exported OpenTelemetry traces
Breaking Changes
- The gateway now defaults to async observability writes to reduce tail latency. To restore previous behavior, set `observability.async_writes = false`.
New Features
- TypeScript evaluators for inference evaluations
- Support for vLLM's new reasoning field
- Aggregated variant usage data (tokens, cost, etc.) in the UI
- Inference cost data in exported OpenTelemetry traces
- Added `export.otlp.traces.include_content` configuration field to include inference content in traces
Full Release Notes
> [!CAUTION] > **Breaking Changes** > > - The gateway now defaults to async observability writes to reduce tail latency: inferences are sent to the client before they are persisted in the database. To restore the previous behavior, set `observability.async_writes = false`. **[[docs]](https://www.tensorzero.com/docs/gateway/configuration-reference)** > [!WARNING] > **Deprecations** > > - Removed the TensorZero Autopilot "Sessions" page from the UI. We recently added a TensorZero MCP that integrates nicely with coding agents, and we'll re-introduce advanced TensorZero Autopilot workflows in a platform-agnostic format soon. **Bug Fixes** - Return HTTP code 429 for rate limiting errors. - Fixed a bug affecting ClickHouse database names with hyphens. (thanks @ianliuy!) **New Features** - Added TypeScript evaluators (for inference evaluations). - Added support for vLLM's new `reasoning` field. - Added aggregated variant usage data (tokens, cost, etc.) to the UI. - Added inference cost data to exported OpenTelemetry traces. (thanks @kimsehwan96!) - Added `export.otlp.traces.include_content` (default false) configuration field to include inference content (e.g. prompts, messages) in exported OpenTelemetry GenAI traces. _& multiple under-the-hood and UI improvements_