{
  "contract_version": "standards.sgit.ai/grammar/v1",
  "generated": "2026-08-24",
  "source": "https://standards.sgit.ai/method/grammar.html",
  "licence": "CC BY 4.0",
  "node_types": [
    {
      "type": "Provision",
      "what": "An article, paragraph or point, carrying its source reference",
      "instantiated": true
    },
    {
      "type": "Definition",
      "what": "A term the instrument defines for its own purposes",
      "instantiated": true
    },
    {
      "type": "Requirement",
      "what": "Something that must be the case",
      "instantiated": true
    },
    {
      "type": "Obligation",
      "what": "Something a named actor must do",
      "instantiated": true
    },
    {
      "type": "Prohibition",
      "what": "Something that must not be done; kept separate from a negated Obligation because they behave differently under exemption",
      "instantiated": true
    },
    {
      "type": "Control",
      "what": "A measure that satisfies a requirement",
      "instantiated": false,
      "note": "Proposed and never instantiated anywhere in this corpus."
    },
    {
      "type": "Actor",
      "what": "The roles the instrument itself defines - provider, deployer, importer, notified body. Not organisations",
      "instantiated": true
    },
    {
      "type": "Amendment",
      "what": "A change to an instrument, as a node in its own right rather than a property of what it changes",
      "instantiated": true
    },
    {
      "type": "FrameworkReference",
      "what": "The crosswalk bridge node of the ontologies-of-ontologies model",
      "instantiated": false,
      "note": "Specified and never built. Zero crosswalks exist on this site."
    }
  ],
  "edge_types": {
    "structural": [
      "defines",
      "defined_in",
      "applies_to",
      "triggers",
      "exempts",
      "references",
      "satisfied_by",
      "in_scope_when"
    ],
    "amendment": [
      "amends",
      "substitutes",
      "inserts",
      "deletes",
      "repealed_by",
      "effective_from",
      "references"
    ],
    "established": [
      "connected_to",
      "observed_on",
      "backed_by",
      "measured_by",
      "grants",
      "reaches",
      "enables",
      "exposes",
      "gives_rise_to",
      "protected_by",
      "conditional_on",
      "defeated_by",
      "owned_by",
      "accepted_by",
      "underwritten_by"
    ]
  },
  "governance_rule": "Where an established edge already fits, use it. A new edge type requires an argument for why no established one fits.",
  "identity": {
    "canonical_id": "positional_hash",
    "positional_hash": "sha256('<instrument-slug>/<alias>') truncated to 16 hex characters. Derived from the ADDRESS. Stable across amendment. This is what a citation and a crosswalk attach to.",
    "content_hash": "sha256 of the provision text. Derived from the TEXT. Moves on amendment - which is the amendment signal.",
    "alias": "A zero-padded human-readable projection of the positional address, e.g. art-026-para-05.",
    "rule": "Address by positional hash, never by array index or display label. Labels are translations; array positions are an accident of parsing. Both failure modes are silent."
  },
  "taxonomy_ontology_split": "Structural containment (bullet -> paragraph -> article -> chapter -> instrument) and semantic relationship (concepts, obligations, external terms) are NOT the same kind of edge. Modelling both as one graph makes a query for what an article contains return concepts, and a query for what a concept relates to return paragraph numbers.",
  "bridge_shape": {
    "required_fields": [
      "from",
      "to",
      "relation",
      "basis",
      "strength",
      "asserted_by",
      "asserted_at",
      "source_content_hash"
    ],
    "strength": "UNDEFINED - no scale exists yet. This blocks the crosswalk browser. Open question Q4.",
    "attaches_to": "positional_hash, so the bridge survives amendment and can report that the text underneath it moved"
  }
}