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

# Installation

Install NeMo Lens using pip, with optional telemetry support depending on your development requirements.

## Basic Install

```bash
pip install nemo-lens
```

This command pulls in only `opentelemetry-api`, the no-op implementation. Instrumented code runs correctly but no spans or metrics are exported. Useful for library authors who want to instrument code without forcing downstream users to install the SDK.

## Install with OTel SDK and OTLP Exporters

```bash
pip install 'nemo-lens[sdk]'
```

Adds `opentelemetry-sdk` and the OTLP exporters (`opentelemetry-exporter-otlp-proto-grpc`, `opentelemetry-exporter-otlp-proto-http`). Required on any rank that actually exports telemetry.

## Install Framework Contrib Extras

```bash
pip install 'nemo-lens[fastapi]'    # FastAPI server auto-instrumentation
pip install 'nemo-lens[aiohttp]'    # aiohttp client auto-instrumentation
```

Each adds the relevant OTel instrumentation package. See [Contrib Helpers](/nemo/lens/user-guide/contrib-helpers) for details.

## Install for Development

```bash
git clone <repo-url>
cd lens
pip install --group dev -e .
pre-commit install
```

The `dev` dependency group includes the SDK, `pytest`, `pytest-cov`, `pre-commit`, and `Ruff`. See [Developer Guide](/nemo/lens/developer-guide/contributing).

## Python Support

`nemo-lens` requires **Python ≥ 3.12**. It uses the PEP 695 `type` statement (e.g., in `src/nemo/lens/strategies.py`), which was introduced in Python 3.12, along with other modern typing features.

## Packaging Notes

`nemo.lens` is a **PEP 420 namespace package**, so it coexists peacefully with NeMo Framework's `nemo.*` packages. The `src/nemo/__init__.py` file contains only an explanatory comment (no code), so it does not shadow other `nemo.*` packages on the path.