# fn-61-document-structure-navigation-and-section-addressability.1 Build shared heading extraction and stable section anchor contract

## Description

Create the shared data layer for section-aware navigation.

Initial slice:

- heading extraction
- stable anchor/slug generation
- section-link building helpers
- typed section metadata for UI/API/SDK/MCP parity
- unit coverage for extraction + slug stability

## Acceptance

- [ ] Shared section extraction logic exists outside DocView-only code
- [ ] Anchor generation is stable and tested
- [ ] Typed section metadata is ready for multiple surfaces
- [ ] Tests cover extraction and slug rules

## Done summary

## Evidence

- Commits:
- Tests:
- PRs:
