> For the complete documentation index, see [llms.txt](https://docs.fastn.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fastn.ai/flow-setup-essentials/designing-a-flow/flow-response-success-and-error.md).
# Flow Response: Success & Error
The **Flow Response** components control what your flow returns when it finishes. Use **Flow Response: Success** to define the payload and HTTP status code returned on a successful run, and **Flow Response: Error** to define what gets returned when the flow encounters a failure. Every API-triggered flow should include both so that callers receive meaningful feedback regardless of the outcome.
**Example Success Definition**
```
Str Status = "success"
Str Message = "Order processed"
Int OrderId = 12345
```
**Example Error Definition**
```
Str Status = "error"
Str ErrorMessage = "Invalid customer email"
```
---
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