> For the complete documentation index, see [llms.txt](https://docs.talus.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.talus.network/reference/move/nexus_workflow/execution_failure.md).
# execution\_failure
* [Enum `WorkflowFailureClass`](#enum-workflowfailureclass)
* [Enum `VertexPaymentSettlement`](#enum-vertexpaymentsettlement)
* [Constants](#constants)
* [Function `workflow_failure_class_retryable`](#function-workflow_failure_class_retryable)
* [Function `workflow_failure_class_terminal_tool_failure`](#function-workflow_failure_class_terminal_tool_failure)
* [Function `workflow_failure_class_terminal_submission_failure`](#function-workflow_failure_class_terminal_submission_failure)
* [Function `vertex_payment_settlement_is_refund`](#function-vertex_payment_settlement_is_refund)
### Enum `WorkflowFailureClass`
Classifies a workflow failure as retryable, a terminal tool failure, or a terminal submission failure.
```move
public enum WorkflowFailureClass has copy, drop, store
```
Variants
Variant `Retryable`Variant `TerminalToolFailure`Variant `TerminalSubmissionFailure`
#### Enum `VertexPaymentSettlement`
Records whether a locked Tool payment is finalized or refunded.
```move
public enum VertexPaymentSettlement has copy, drop, store
```
Variants
Variant `Finalize`Variant `Refund`
#### Constants
```move
#[error]
const EErrEvalReasonMismatch: vector = b"The _err_eval reason is not canonical inline data";
```
#### Function `workflow_failure_class_retryable`
Returns the `Retryable` workflow failure class value.
```move
public fun workflow_failure_class_retryable(): nexus_workflow::execution_failure::WorkflowFailureClass
```
#### Function `workflow_failure_class_terminal_tool_failure`
Returns the `TerminalToolFailure` workflow failure class value.
```move
public fun workflow_failure_class_terminal_tool_failure(): nexus_workflow::execution_failure::WorkflowFailureClass
```
#### Function `workflow_failure_class_terminal_submission_failure`
Returns the `TerminalSubmissionFailure` workflow failure class value.
```move
public fun workflow_failure_class_terminal_submission_failure(): nexus_workflow::execution_failure::WorkflowFailureClass
```
#### Function `vertex_payment_settlement_is_refund`
Returns whether a vertex payment settlement refunds a locked Tool payment.
```move
public fun vertex_payment_settlement_is_refund(self: &nexus_workflow::execution_failure::VertexPaymentSettlement): bool
```
---
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