@markschema/mdshape

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min ​

Type: list

Signature: list(...).min(size)

What It Is ​

list(...).min(size) enforces a minimum list length while preserving typed list items. The schema combines operators such as document(), heading(), metadataObject(), and list() to map 1 h1 heading and frontmatter content into top-level keys title and frontmatter for this min behavior. If parsing fails, the result carries issue codes like list_too_small, giving the caller precise debugging context for min paths.

When to Use ​

Use list(...).min(size) when your list is required to contain at least N items and you want deterministic validation failures. Avoid it when empty lists are acceptable business-wise, because min constraints will always reject undersized input. It pairs well with document(), heading(), metadataObject(), and list() to keep extraction boundaries explicit while preserving typed output for downstream code.

list(...).min(size) ​

Input Markdown ​

md
# RUNBOOK: List Min

## 2. LABELS

- urgent
- incident

Schema ​

ts
import { md } from '@markschema/mdshape'

const schema = md.document({
  title: md.heading(1),
  labels: md
    .section('2. LABELS')
    .list(md.string().min(3))
    .pipeline(md.list(md.string().min(3)).min(2)),
})

Result ​

Success ​

json
{
  "success": true,
  "data": {
    "title": "RUNBOOK: List Min",
    "labels": [
      "urgent",
      "incident"
    ]
  }
}

Error ​

Failure trigger: The input violates one or more constraints declared in the schema; use issues[].path and issues[].code to locate the exact failing node.

json
{
  "success": false,
  "error": {
    "issues": [
      {
        "code": "missing_heading",
        "message": "Missing heading with depth 1",
        "path": [
          "title"
        ],
        "line": 1,
        "position": {
          "start": {
            "line": 1,
            "column": 1
          }
        }
      }
    ]
  }
}