> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/nemo/guardrails/_mcp/server.

# Colang Standard Library (CSL)

> The Colang Standard Library (CSL) provides an abstraction from the underlying event and action layer and offers a semantic interface to design interaction patterns between the bot

The Colang Standard Library (CSL) provides an abstraction from the underlying event and action layer and offers a semantic interface to design interaction patterns between the bot and the user. Currently, there are the following library files available under `nemoguardrails/colang/v2_x/library/` ([GitHub link](https://github.com/NVIDIA-NeMo/Guardrails/tree/develop/nemoguardrails/colang/v2_x/library)):

#### [Core Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/core)

Core user, bot, wait, and notification flows.

#### [Timing Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/timing)

Wait, timer, and silence detection flows.

#### [LLM Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/lmm)

LLM continuation and utility flows.

#### [Avatar Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/avatars)

Gesture, posture, and avatar-related flows.

#### [Guardrail Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/guardrails)

Standard guardrail flow definitions.

#### [Attention Flows](/configure-guardrails/colang/colang-2/language-reference/the-standard-library/attention)

User attention tracking and checks.

To use the flows defined in these libraries you have two options:

* \[Recommended] Import the standard library files using the import statement: e.g. `import llm`
* Copy the corresponding `*.co` file directly inside your Colang script directory.

Note that the `import <library>` statement will import all available flows of the corresponding library.

> The Colang Standard Library (CSL) provides an abstraction from the underlying event and action layer and offers a semantic interface to design interaction patterns between the bot

## Docs

- [Fundamental Core Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/core.md): The core library that contains all relevant flows related to user and bot utterance events and actions.
- [Timing Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/timing.md): Flows related to timing and reacting to periods of silence.
- [LLM Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/lmm.md): Trigger a bot utterance similar to given text
- [Interactive Avatar Modality Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/avatars.md): **User Event Flows**
- [Guardrail Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/guardrails.md): Flows to guardrail user inputs and LLM responses.
- [User Attention Flows](https://docs.nvidia.com/nemo/guardrails/v0.24.0/configure-guardrails/colang/colang-2/language-reference/the-standard-library/attention.md): Flows to handle user attention.