---
id: LANG-23
family: GR-LANG
level: extended
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/gr-lang/lang-23
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# LANG-23 — Only a `$`-rooted JSONPath query unwraps a list to its first match

*GR-LANG (Part I) · level: extended · profiles: runtime · added in 1.0*

## The rule

> **Normative.** This is the rule.
>
> 1. An extractor reduces a list result to its first match only where its engine is jsonpath, the path is `$`-rooted, and extract-all is off.
>
> 2. A property-path engine delivers a list result whole, even for a `$`-prefixed path, and a jsonpath engine that falls back to property-path resolution never unwraps.
>
> 3. The extractor's reported JSONPath flag reports the `$` prefix alone and is independent of the engine in force.

## Related rules

- Names: LANG-14, LANG-15

---

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.