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> For a complete documentation index, see https://docs.nvidia.com/nemo/relay/llms.txt.
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# Function nemo_relay_scope_register_llm_conditional_execution_guardrail

> Register a scope-local LLM conditional execution guardrail.

Generated from `cargo doc --no-deps -p nemo-relay -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

<pre />

Register a scope-local LLM conditional execution guardrail.

## Parameters

* `scope_uuid`: UUID of the target scope (null-terminated C string).
* `name`: Unique guardrail name.
* `priority`: Execution priority (lower runs first).
* `cb`: Conditional callback.
* `user_data`: Opaque pointer passed to `cb`.
* `free_fn`: Optional destructor for `user_data`.

The callback is fallible. To signal an internal callback failure instead of allow/reject, call [`crate::error::nemo_relay_set_last_error_message`](/reference/api/rust-library-reference/nemo-relay-ffi/error/fn-nemo-relay-set-last-error-message) from C and return null.

## Safety

`scope_uuid` and `name` must be valid C strings. `cb` must be a valid function pointer.