Nemo engine

Default NeMo Guardrails engine implementation.

Authors

Kevin Yauris (kevin.yauris@gdplabs.id) Moch. Nauval Rizaldi Nasril (moch.n.r.nasril@gdplabs.id)

References

[1] https://github.com/NVIDIA/NeMo-Guardrails

NemoGuardrailEngine(config=None)

Bases: GuardrailEngine

Default engine that keeps current NeMo Guardrails behavior.

This engine implements the GuardrailEngine protocol to provide NeMo Guardrails functionality for content safety checking.

Attributes:

Name	Type	Description
config	NemoGuardrailEngineConfig	Engine configuration specifying what content types to check.
rails	LLMRails | None	LLMRails instance.

Initializes a new instance of the NemoGuardrailEngine class.

Parameters:

Name	Type	Description	Default
config	NemoGuardrailEngineConfig | None	NemoGuardrailEngineConfig with both base and NeMo-specific settings. Defaults to None.	None

check_input(content, **kwargs) async

Check input content for safety violations.

This method implements NeMo Guardrails checking for user input such as query content, context, or prompts before sending to LLM.

Parameters:

Name	Type	Description	Default
content	str	The input text to evaluate for safety.	required
**kwargs	Any	Additional engine-specific parameters.	{}

Returns:

Name	Type	Description
GuardrailResult	GuardrailResult	GuardrailResult indicating if content is safe, with reason if unsafe.

Raises:

Type	Description
RuntimeError	If the guardrail engine is not initialized.

check_output(content, **kwargs) async

Check output content for safety violations.

This method implements NeMo Guardrails checking for system output such as LLM responses, generated text, or static messages before showing to users.

Parameters:

Name	Type	Description	Default
content	str	The output text to evaluate for safety.	required
**kwargs	Any	Additional engine-specific parameters.	{}

Returns:

Name	Type	Description
GuardrailResult	GuardrailResult	GuardrailResult indicating if content is safe, with reason if unsafe.

Raises:

Type	Description
RuntimeError	If the guardrail engine is not initialized.

NemoGuardrailEngineConfig(guardrail_mode=GuardrailMode.INPUT_ONLY, config_dict=None, colang_config=None, denial_phrases=None, topic_safety_mode=None, allowed_topics=None, denied_topics=None, include_core_restrictions=None, core_restriction_categories=None) dataclass

Bases: BaseGuardrailEngineConfig

NeMo-specific configuration that extends base guardrail config.

This config inherits the basic guardrail_mode from BaseGuardrailEngineConfig and adds NeMo-specific settings for advanced guardrail functionality.

Attributes:

Name	Type	Description
config_dict	dict[str, Any] | None	Dictionary of NeMo-specific configuration.
colang_config	str | None	Optional Colang configuration string.
denial_phrases	list[str] | None	Phrases that indicate blocked content.
topic_safety_mode	TopicSafetyMode | str | None	Topic safety mode.
allowed_topics	list[str] | None	List of allowed topics for responses.
denied_topics	list[str] | None	List of denied topics for responses.
include_core_restrictions	bool | None	Whether to include core safety restrictions.
core_restriction_categories	list[str] | None	List of enabled core restriction categories.

init_guardrails_provider_registration()

Register global NeMo Guardrails chat provider once.

This avoids redundant registration per preset/component. Safe to call once during process initialization.

Returns:

Name	Type	Description
bool	bool	True if registration succeeded, False otherwise.