---
id: ERR-1
family: RT-ERR
level: core
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/rt-err/err-1
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# ERR-1 — A node-level failure becomes an error output, not a thrown failure

*RT-ERR (Part II) · level: core · profiles: runtime · added in 1.0*

The error edge is a data channel, not an exception channel. A node that fails in a routable way still finishes; the verdict travels on its output.

## The rule

> **Normative.** This is the rule.
>
> 1. A failure a node signals as a node-level error is converted into an error-status output for that node and does not propagate out of the node.
>
> 2. The node's lifecycle is reported as completed, not failed; it finished, and the error verdict rides its output.


## What it means

A failure a node signals in a routable way never shows up as a failed node.
The node's own lifecycle record reports it as completed — the same status a
node that raised nothing at all would report — because the node did finish;
only the value on its output carries the verdict. A reader expecting the
node's own status to reflect the failure will read the trail backwards:
`failed` is reserved for a failure that escapes the node altogether (ERR-3),
never for one that converted cleanly.

Where the node also has an error edge, ERR-7 governs what happens to that
output next.

## Example

A node raises an ordinary failure inside its own run.

```json title="The status trail broadcast for the node's own run" verdict="completed"
["running", "completed"]
```

The trail never reaches `failed`; that status is reserved for a failure that
escapes the node entirely, not one converted to an output.

## Related rules

- Names: ERR-3, ERR-7
- Referenced by: ERR-3, ERR-4, ERR-5, ERR-6

---

Rule identifiers are permanent and are never renumbered. This specification carries
no implementation status: each implementation publishes its own standing against
these rules. Licensed CC BY 4.0.