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# Ensure Idempotency in context.run

Business logic should be idempotent due to potential retries in distributed systems. In other words, **when a workflow runs twice with the same input, the end result should be the same as if the workflow only ran once**.

In the example below, the `someWork` function must be idempotent:

<CodeGroup>

```typescript api/workflow/route.ts
export const { POST } = serve<string>(async (context) => {
  const input = context.requestPayload

  await context.run("step-1", async () => {
    return someWork(input)
  })
})
```

```python main.py
@serve.post("/api/example")
async def example(context: AsyncWorkflowContext[str]) -> None:
    input = context.request_payload

    async def _step_1() -> None:
        return await some_work(input)

    await context.run("step-1", _step_1)

```

</CodeGroup>

Imagine that `someWork` executes once and makes a change to a database. However, before the database had a chance to respond with the successful change, the connection is lost. Your Workflow cannot know if the database change was successful or not. The caller has no choice but to retry, which will cause `someWork` to run twice.

If `someWork` is not idempotent, this could lead to unintended consequences. For example duplicated records or corrupted data. Idempotency is crucial to maintaining the integrity and reliability of your workflow.