---
id: DATA-3
family: RT-DATA
level: core
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/rt-data/data-3
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# DATA-3 — A trigger edge carries no data

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

## The rule

> **Normative.** This is the rule.
>
> 1. A trigger edge conveys only that its source completed.
>
> 2. It delivers no value, and no input port on its target is ever filled by one.


## What it means

A trigger edge carries only the fact that its source finished, never a
value — and that holds even where the edge's target handle names an
ordinary input port. Pointing a trigger edge at a port that looks like a
data port does not make it one: the port is never filled.

## Example

`node_a` produces an output, and a trigger edge wires it to `node_z`'s
`data` port.

```json title="What node_a produced" verdict="produced"
{"result": "alpha"}
```

```json title="What node_z receives on the wired port" verdict="empty"
{}
```

---

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.