---
id: capability.wiki.page-model
name: Backend-Neutral Wiki Page Model
summary: A Markdown-first but stretchable page model with stable identity separate from placement and layered provenance, spanning prose to typed-graph and computational shapes.
owner: shard-wiki
status: draft
domain: helix_forge
tags: [wiki, page-model, identity, provenance, markdown, shard-wiki]

maturity:
  discovery:
    current: D5
    target: D6
    confidence: high
    rationale: >
      Page shapes (prose, typed records, typed-graph, inline-embedded, non-Markdown,
      and four computational shapes) plus identity != placement and layered provenance
      are specified and grounded in the dive research.
  availability:
    current: A2
    target: A5
    confidence: medium
    rationale: >
      Identity/Placement/Span/Page and layered ProvenanceEnvelope exist as a source
      module; richer shapes (typed-graph, notebook) are modeled but not all built.

external_evidence:
  completeness:
    level: C2
    name: Partial
    confidence: medium
    basis: scope_vs_intent_and_consumer_expectations
    satisfied_expectations:
      - stable identity distinct from placement and from content fingerprint
      - layered (effective-vs-own) provenance with near-zero per-span cost
    broken_expectations:
      - non-prose shapes (typed-graph, notebook, inline-embedded) not fully realized
    out_of_scope_expectations:
      - rendering / presentation
  reliability:
    level: R1
    confidence: low
    basis: consumer_quality_signals
    known_reliability_risks:
      - prose shape is the only exercised path so far

discovery:
  intent: >
    One backend-neutral lingua franca every consumer sees; every shape reduces to
    (content|source, structure, provenance envelope, optional derivation rule).
  includes:
    - page identity (stable handle) vs placement (N paths/shards) vs equivalence (fingerprint)
    - layered provenance envelope (page + span deltas)
    - page-shape taxonomy incl. computational shapes
  excludes:
    - deriving identity from content (a fingerprint identifies a version, not a page)
  use_cases:
    - "shard-wiki UseCaseCatalog UC-34, UC-39, UC-44..UC-49, UC-55, UC-73, UC-83, UC-84"

availability:
  current_level: A2
  target_level: A5
  current_artifacts:
    - "shard-wiki/src/shard_wiki/model/"
    - "shard-wiki/src/shard_wiki/provenance/"
  consumption_modes:
    - source module

relations:
  supports:
    - capability.wiki.adapter-contract
    - capability.wiki.shard-orchestration

evidence:
  documentation:
    - "shard-wiki/spec/CoreArchitectureBlueprint.md (Section 7)"
    - "shard-wiki/spec/FederationRequirements.md (ADR-02, ADR-04)"
  tests:
    - "shard-wiki/tests/test_model.py"
    - "shard-wiki/tests/test_provenance.py"

consumer_guidance:
  recommended_for:
    - a portable, provenance-carrying representation of wiki pages across backends
  not_recommended_for:
    - cases needing a single canonical path per page (use identity, not path)
  known_limitations:
    - non-prose shapes specified ahead of implementation
---

# Backend-Neutral Wiki Page Model

The top narrow waist: a Markdown-first model that stretches to typed records, typed-graph
statements, inline-embedded objects, non-Markdown assets, and computational shapes. Identity
is a stable handle; placement and equivalence are separate mechanisms; provenance is layered
(effective = page envelope + span delta).

## Assessment notes

### Discovery
Specified in CoreArchitectureBlueprint Section 7 and FederationRequirements ADR-02/04.

### Availability
`model/` + `provenance/` ship the prose path and the layered envelope today.