---
id: DYN-3
family: GR-DYN
level: extended
profiles: [storage-api]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/gr-dyn/dyn-3
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# DYN-3 — Dynamic port names are constrained and unique across the node

*GR-DYN (Part I) · level: extended · profiles: storage-api · added in 1.0*

## The rule

> **Normative.** This is the rule.
>
> 1. A dynamic port name begins with an ASCII letter and continues with ASCII letters, digits or underscores.
>
> 2. It must not be a reserved name, and it must be unique across the union of the node's dynamic input and dynamic output names: an input and an output on the same node may not share a name.
>
> 3. A definition that breaks any of these is refused.

---

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.