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# Enum Flow Error

> The error type for all NeMo Relay runtime operations.

Generated from `cargo doc --no-deps -p nemo-relay -p nemo-relay-adaptive -p nemo-relay-ffi`.

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The error type for all NeMo Relay runtime operations.

Each variant represents a distinct failure mode that callers can match on to determine the appropriate recovery strategy.

## Variants

### `AlreadyExists(String)`

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A resource with the given name is already registered.

Returned when attempting to register a guardrail, intercept, or subscriber with a name that is already in use. Deregister the existing entry first, or choose a different name.

### `NotFound(String)`

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The requested resource was not found.

Returned when attempting to remove a scope handle by UUID that does not exist in the scope stack, or when looking up a non-existent entity.

### `InvalidArgument(String)`

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A function argument was invalid for the requested operation.

Returned when a provided value is well-formed but violates an API precondition, such as attempting to pop a scope that is not currently at the top of the stack.

### `ScopeStackEmpty`

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The scope stack is empty.

This should not occur under normal operation because the root scope is always present and cannot be removed.

### `GuardrailRejected(String)`

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A conditional execution guardrail rejected the operation.

The contained string is the rejection reason provided by the guardrail. This is returned during `tool_call_execute` or `llm_call_execute` when a conditional guardrail returns `Some(reason)`.

### `Internal(String)`

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An internal runtime error (e.g., lock poisoning).

## Trait Implementations

### `impl Debug for FlowError`

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#### `fmt`

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### `impl Display for FlowError`

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#### `fmt`

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### `impl Error for FlowError`

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#### `source`

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#### `description`

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#### `cause`

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#### `provide`

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### `impl From<FlowError> for AtofExporterError`

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#### `from`

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### `impl From<FlowError> for OpenInferenceError`

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#### `from`

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### `impl From<FlowError> for OpenTelemetryError`

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#### `from`

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