• Identify page-internal content units with stable section-level identity.
• Distinguish sections from pages and parent containers.
• Attach section-level metadata such as name, description, intent, interpretive frame, order, and hierarchy.
• Represent nested content structure when a page contains meaningful subsections.

Section metadata provides page-internal semantic context. It should not be treated as a standalone page declaration unless explicitly used in a page-equivalent context.

• Provide stable identity through id.
• Remain semantically coherent as a page-internal content unit.
• Remain distinct from page, which identifies a standalone addressable resource.
• Use parent context when section hierarchy or containment needs to be declared.
• Use hierarchy fields contextually when order, level, or nesting matters.

A section may have its own contextual metadata, but it remains subordinate to page context unless explicitly declared otherwise.

• id — required; stable identifier for the section within the page or declared section hierarchy.

Recommended fields include:

• name — human-readable section name or structured naming block.
• description — summary of the section's contents or purpose.
• intent — statement describing the section's purpose or function.
• interpretiveFrame — interpretive framing that applies specifically to the section.
• parent — identifier or object reference for the parent page or parent section.
• order — explicit ordering index for the section in lists, arrays, or navigation.
• level — hierarchical depth of the section within the page or section tree.

The title field is retained as a compatibility field. It should not displace name as the preferred MSP-1 naming term. The label field may be used for outline markers or structural labels such as 1.2, A.3, or Appendix B.

• AI agents should treat section as a page-internal semantic unit unless explicitly declared as page-equivalent.
• Agents should use id as the minimal section identity field.
• Agents should prefer name over compatibility title when both are present.
• Section-level metadata may refine page-level context when more specific.
• Missing optional section metadata should trigger fallback to page-level context rather than invalidation.
• Legacy flat-string section values may receive an advisory warning and be interpreted as simple section labels when graceful degradation is appropriate.

Section metadata supports fine-grained interpretation without requiring agents to infer internal page structure only from headings or surrounding content.

• page — identifies the standalone addressable resource that contains or contextualizes the section.
• parent — identifies the containing page or higher-level section.
• id — provides stable section identity.
• name — provides the preferred human-readable section label.
• description — summarizes what the section covers.
• intent — explains the purpose or function of the section.
• interpretiveFrame — guides contextual interpretation of the section.
• canonical — may identify a preferred authoritative URL representation if the section is independently addressable or represented.

Do not confuse section with page or parent. section identifies a meaningful subdivision within a page; page identifies the standalone addressable resource; parent identifies the containing page or higher-level section.

{
  "section": {
    "id": "introduction"
  }
}

Section with metadata:

{
  "section": {
    "id": "lighting-basics",
    "name": "Lighting Basics",
    "description": "Introduction to natural and artificial lighting principles.",
    "intent": "Provide foundational understanding for new photographers.",
    "parent": "lighting-guide",
    "order": 1
  }
}

Nested sections:

{
  "sections": [
    {
      "id": "studio-lighting",
      "name": "Studio Lighting",
      "parent": "lighting-guide"
    },
    {
      "id": "studio-modifiers",
      "name": "Lighting Modifiers",
      "parent": "studio-lighting"
    }
  ]
}

• It expresses section as an object.
• It provides required id for stable section identity.
• It treats title as a compatibility field rather than the preferred naming term.
• It uses hierarchy fields such as parent, order, and level consistently when present.
• It does not confuse section-level metadata with page-level or parent metadata.