@mastra/core/dist/docs/references/reference-workflows-run-methods-resume.md

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# Run.resume()

The `.resume()` method resumes a suspended workflow run with new data, allowing you to continue execution from a specific step.

## Usage example

```typescript
const run = await workflow.createRun()

const result = await run.start({ inputData: { value: 'initial data' } })

if (result.status === 'suspended') {
  const resumedResults = await run.resume({
    resumeData: { value: 'resume data' },
  })
}
```

## Parameters

**resumeData** (`z.infer<TResumeSchema>`): Data for resuming the suspended step

**step** (`Step<string, any, any, TResumeSchema, any, TEngineType> | [...Step<string, any, any, any, any, TEngineType>[], Step<string, any, any, TResumeSchema, any, TEngineType>] | string | string[]`): The step(s) to resume execution from. Can be a Step instance, array of Steps, step ID string, or array of step ID strings

**requestContext** (`RequestContext`): Request Context data to use when resuming

**retryCount** (`number`): Optional retry count for nested workflow execution

**forEachIndex** (`number`): Target a specific iteration of a suspended \`.foreach()\` step. Pass the zero-based index of the iteration you want to resume; other iterations remain suspended. Omit this field to resume all suspended iterations of the step with the same \`resumeData\`.

**tracingContext** (`TracingContext`): Tracing context for creating child spans and adding metadata. Automatically injected when using Mastra's tracing system.

**tracingContext.currentSpan** (`Span`): Current span for creating child spans and adding metadata. Use this to create custom child spans or update span attributes during execution.

**tracingOptions** (`TracingOptions`): Options for Tracing configuration.

**tracingOptions.metadata** (`Record<string, any>`): Metadata to add to the root trace span. Useful for adding custom attributes like user IDs, session IDs, or feature flags.

**tracingOptions.requestContextKeys** (`string[]`): Additional RequestContext keys to extract as metadata for this trace. Supports dot notation for nested values (e.g., 'user.id').

**tracingOptions.traceId** (`string`): Trace ID to use for this execution (1-32 hexadecimal characters). If provided, this trace will be part of the specified trace.

**tracingOptions.parentSpanId** (`string`): Parent span ID to use for this execution (1-16 hexadecimal characters). If provided, the root span will be created as a child of this span.

**tracingOptions.tags** (`string[]`): Tags to apply to this trace. String labels for categorizing and filtering traces.

**outputOptions** (`OutputOptions`): Options for output configuration.

**outputOptions.includeState** (`boolean`): Whether to include the workflow run state in the result.

## Returns

**result** (`Promise<WorkflowResult<TState, TOutput, TSteps>>`): A promise that resolves to the workflow execution result containing step outputs and status

**traceId** (`string`): The trace ID associated with this execution when Tracing is enabled. Use this to correlate logs and debug execution flow.

**spanId** (`string`): The root span ID associated with this execution when Tracing is enabled. Use this for span-level lookup and correlation.

## Extended usage example

```typescript
if (result.status === 'suspended') {
  const resumedResults = await run.resume({
    step: result.suspended[0],
    resumeData: { value: 'resume data' },
  })
}
```

> **Note:** When exactly one step is suspended, you can omit the `step` parameter and the workflow will automatically resume that step. For workflows with multiple suspended steps, you must explicitly specify which step to resume.

### Resuming a single [`.foreach()`](https://mastra.ai/reference/workflows/workflow-methods/foreach) iteration

When a [`.foreach()`](https://mastra.ai/reference/workflows/workflow-methods/foreach) step suspends across multiple iterations, use `forEachIndex` (zero-based) to resume one iteration at a time with different `resumeData`. Iterations not targeted by `forEachIndex` remain suspended until resumed.

```typescript
// Resume only the second iteration (index 1) with its own data
await run.resume({
  step: 'approve',
  resumeData: { ok: true },
  forEachIndex: 1,
})

// Later, resume the first iteration with different data
await run.resume({
  step: 'approve',
  resumeData: { ok: false },
  forEachIndex: 0,
})
```

If `forEachIndex` is omitted, every suspended iteration of the step is resumed with the same `resumeData`.

## Related

- [Workflows overview](https://mastra.ai/docs/workflows/overview)
- [Workflow.createRun()](https://mastra.ai/reference/workflows/workflow-methods/create-run)
- [Suspend and resume](https://mastra.ai/docs/workflows/suspend-and-resume)
- [Human in the loop](https://mastra.ai/docs/workflows/human-in-the-loop)