> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.nvidia.com/nemo/relay/llms.txt.
> For full documentation content, see https://docs.nvidia.com/nemo/relay/llms-full.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/nemo/relay/_mcp/server.

# Highlights

This page summarizes the notable capabilities in the current release
documentation set.

## NeMo Relay 0.3

NeMo Relay 0.3 adds first-party guardrails, richer trajectory export, adaptive
plugin workflows, and clearer integration support for agent runtimes.

### Breaking Changes

* The project was renamed to NeMo Relay across documentation, package guidance,
  and CLI-facing surfaces.
* The core runtime registry surface was narrowed. Applications should use the
  documented middleware, intercept, subscriber, and plugin APIs instead of broad
  registry access.
* Native subscriber delivery is now non-blocking. Event construction remains
  synchronous, but subscriber callbacks and exporter work are queued on a
  process-wide background dispatcher. Applications and tests that depend on
  subscriber side effects must call the subscriber flush API before reading
  captured events, files, or exported trace output.

### Guardrails

* Added the built-in `nemo_guardrails` plugin contract for installing NeMo
  Guardrails behavior through NeMo Relay plugin configuration.
* Added a remote NeMo Guardrails backend for deployments that call an external
  guardrails service.
* Added CLI editor support for guardrails plugin configuration.
* Added guardrail scopes for conditional guardrails so trace output shows
  guardrail execution boundaries more clearly.
* Integrated security guardrails around managed agent calls.

### Observability

* Exposed canonical ATOF event JSON across bindings so applications can consume
  the same event shape from Rust, Python, and Node.js.
* Upgraded ATIF exporters to ATIF v1.7 with nested subagent support.
* Added first-class S3-compatible storage export for ATIF traces.
* Added streaming LLM chunk marks for more precise streaming trace inspection.
* Fixed LLM start event ordering so managed LLM start events are emitted before
  execution intercepts.
* Fixed ATIF tool-observation correlation.

### Plugins And Adaptive Runtime

* Enabled the adaptive plugin for the CLI and OpenClaw workflows.
* Added CLI editor support for adaptive plugin configuration.
* Added a Python context manager for plugin initialization and teardown.

### Integrations

* Improved LangChain serialization for wrapped requests and responses.
* Preserved OpenClaw tool call replay visibility with the upgrade to OpenClaw 2026.5.26
* Updated the launch banner to use `NEMO RELAY`.

### Documentation And Tooling

* Switched the documentation site to Fern and consolidated Fern publishing.
* Added broken-link validation for Fern documentation.
* Added agent runtime primer, trace incident runbook, plugin-building, migration,
  and adaptive tuning guidance.
* Added built-in guardrails plugin documentation.
* Added CI path filters, CLI draft release assets, dependency updates, and ATIF
  S3 storage test coverage.

The complete changelog and release artifacts can be viewed on
[GitHub Releases](https://github.com/NVIDIA/NeMo-Relay/releases).