{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://fhir-fli.github.io/fhir_fli_documentation/orbweaver/schema/topic.schema.json",
  "title": "Orbweaver topic",
  "description": "One orbweaver topic file (`assets/books/<book>/topics/<name>.yaml`): a page or pages of typed blocks. If a file validates against this schema the app parses and renders it. Unknown keys are errors because the renderer silently ignores them.",
  "type": "object",
  "properties": {
    "topic": {
      "description": "A topic: one or more pages of blocks.",
      "type": "object",
      "properties": {
        "id": {
          "description": "Logical id, kebab-case, unique across all books; the target of `topic:<id>` links.",
          "type": "string",
          "pattern": "^[a-z0-9][a-z0-9_-]*$"
        },
        "title": {
          "description": "Page title.",
          "type": "string"
        },
        "list_subtitle": {
          "description": "Subtitle shown under the title in the contents list.",
          "type": "string"
        },
        "version": {
          "type": "string"
        },
        "last_reviewed": {
          "description": "Source version string (e.g. `pocketbook v1.7`), not a date.",
          "type": "string"
        },
        "tags": {
          "description": "Search keywords.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "aliases": {
          "description": "Alternative names, weighted like tags in search.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "category": {
          "description": "Clinical category (metadata).",
          "type": "string",
          "enum": [
            "universal",
            "medical",
            "trauma",
            "critical_care"
          ],
          "default": "universal"
        },
        "layout": {
          "description": "`scroll` = one continuous column; `paged` = each page snaps to one screen.",
          "type": "string",
          "enum": [
            "scroll",
            "paged"
          ],
          "default": "scroll"
        },
        "font_family": {
          "description": "Body typeface; must be a font the app bundles (`RobotoCondensed`).",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "page_number": {
          "description": "Printed page number (single-page form only).",
          "type": "integer"
        },
        "pages": {
          "description": "Pages, each with its own `page_number` and `blocks` (preferred form).",
          "type": "array",
          "items": {
            "$ref": "#/$defs/page"
          },
          "minItems": 1
        },
        "blocks": {
          "description": "Blocks of a single-page topic (legacy form; use `pages` instead).",
          "type": "array",
          "items": {
            "$ref": "#/$defs/block"
          },
          "minItems": 1
        }
      },
      "required": [
        "id",
        "title"
      ],
      "additionalProperties": false,
      "oneOf": [
        {
          "required": [
            "pages"
          ],
          "not": {
            "anyOf": [
              {
                "required": [
                  "blocks"
                ]
              },
              {
                "required": [
                  "page_number"
                ]
              }
            ]
          }
        },
        {
          "required": [
            "blocks"
          ],
          "not": {
            "required": [
              "pages"
            ]
          }
        }
      ]
    }
  },
  "required": [
    "topic"
  ],
  "additionalProperties": false,
  "$defs": {
    "color": {
      "description": "Colour as `0xAARRGGBB`, `0xRRGGBB` or `#RRGGBB`.",
      "type": "string",
      "pattern": "^(0[xX]|#)?[0-9A-Fa-f]{6}([0-9A-Fa-f]{2})?$"
    },
    "palette": {
      "description": "Palette overrides, role → colour. Cascades book → chapter → topic → block; any role may be overridden and custom roles added. Common roles: accent, accent_fill, accent_branch, alert, alert_fill, alert_text, severity_{mild,moderate,severe}_{header,tile}, provider_{emt,aemt,intermediate,paramedic,critical_care,any}, pop_{adult,peds}, warning_{safety,caution}, flow_{decision,entry,convergence}, cc_link_{fill,border}, note_{fill,border,text}, danger_text.",
      "type": "object",
      "additionalProperties": {
        "$ref": "#/$defs/color"
      }
    },
    "age_band": {
      "description": "One age row of a banded entry node.",
      "type": "object",
      "properties": {
        "label": {
          "description": "Age row label, e.g. `Adult (14+)`.",
          "type": "string"
        },
        "value": {
          "description": "Threshold for that age, e.g. `90 mmHg`.",
          "type": "string"
        },
        "cc": {
          "description": "Optional Critical-Care value shown in a fused lavender column (needs `cc_title` on the node).",
          "type": "string"
        }
      },
      "required": [
        "label",
        "value"
      ],
      "additionalProperties": false
    },
    "flow_node": {
      "description": "A flowchart node: entry, decision, or a continuation step.",
      "type": "object",
      "properties": {
        "text": {
          "description": "Node text.",
          "type": "string"
        },
        "shape": {
          "description": "Node outline.",
          "type": "string",
          "enum": [
            "rectangle",
            "rounded_rectangle",
            "stadium",
            "diamond"
          ],
          "default": "rectangle"
        },
        "bands": {
          "description": "Age-tiered thresholds drawn as a striped mini-table inside the node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/age_band"
          }
        },
        "cc_title": {
          "description": "Header of the fused Critical-Care column when `bands` carry `cc` values, e.g. `Or MAP`.",
          "type": "string"
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "action": {
      "description": "An action tile.",
      "type": "object",
      "properties": {
        "text": {
          "description": "Action text.",
          "type": "string"
        },
        "kind": {
          "description": "Action category (icon/styling).",
          "type": "string",
          "enum": [
            "procedure",
            "medication_administration",
            "diagnostic",
            "assessment",
            "referral",
            "communication"
          ],
          "default": "procedure"
        },
        "provider_level": {
          "description": "Minimum provider level cleared for the intervention (WVEMS badge): E = EMT, A = AEMT, I = Intermediate, P = Paramedic, P(CC) or CC = Critical Care. Omit for any level.",
          "type": "string",
          "enum": [
            "E",
            "A",
            "I",
            "P",
            "P(CC)",
            "CC"
          ]
        },
        "timing": {
          "description": "Annotation such as `every 5 min`.",
          "type": "string"
        },
        "condition": {
          "description": "Annotation such as `if VT/VF`.",
          "type": "string"
        },
        "peds_only": {
          "description": "Pink `Peds` side tab on the right edge of the tile.",
          "type": "boolean",
          "default": false
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "warning": {
      "description": "Side warning callout flanking a node.",
      "type": "object",
      "properties": {
        "type": {
          "description": "`safety` = red octagon on the left (scene safety, BSI); `caution` = purple trapezoid on the right (capacity, refusal, Critical-Care cross-reference). Only the first of each type renders.",
          "type": "string",
          "enum": [
            "safety",
            "caution"
          ]
        },
        "text": {
          "description": "Callout text.",
          "type": "string"
        }
      },
      "required": [
        "type",
        "text"
      ],
      "additionalProperties": false
    },
    "convergence_bullet": {
      "description": "A bullet inside a convergence node.",
      "type": "object",
      "properties": {
        "text": {
          "description": "Bullet text.",
          "type": "string"
        },
        "link_id": {
          "description": "Visual cross-reference cue (underline); the app does not navigate on it.",
          "type": "string"
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "convergence_exit": {
      "description": "A labelled arrow leaving the convergence node.",
      "type": "object",
      "properties": {
        "label": {
          "description": "Arrow label, e.g. `Improvement` / `No change`.",
          "type": "string"
        },
        "loopback": {
          "description": "`id` of a branch to loop back to. Omit for a forward arrow into `post_convergence`.",
          "type": "string"
        }
      },
      "required": [
        "label"
      ],
      "additionalProperties": false
    },
    "convergence": {
      "description": "The node where branches reconverge (or a post-convergence box).",
      "type": "object",
      "properties": {
        "text": {
          "description": "Node text, e.g. `Re-assess ABC`.",
          "type": "string"
        },
        "shape": {
          "description": "Node outline.",
          "type": "string",
          "enum": [
            "rectangle",
            "rounded_rectangle",
            "stadium",
            "diamond"
          ],
          "default": "rounded_rectangle"
        },
        "bullets": {
          "description": "Bullet list inside the node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/convergence_bullet"
          }
        },
        "exits": {
          "description": "Labelled arrows leaving the node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/convergence_exit"
          }
        },
        "warnings": {
          "description": "Side callouts flanking the node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/warning"
          }
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "cc_link": {
      "description": "Lavender Critical-Care reference pill under the convergence.",
      "type": "object",
      "properties": {
        "text": {
          "description": "Pill text, e.g. `Sepsis`; may carry a `[text](topic:…)` link.",
          "type": "string"
        },
        "link_id": {
          "description": "Visual cross-reference cue (underline).",
          "type": "string"
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "dose_row": {
      "description": "One row of the dose reference strip under a flowchart.",
      "type": "object",
      "properties": {
        "drug": {
          "type": "string"
        },
        "dose": {
          "type": "string"
        },
        "route": {
          "type": "string"
        },
        "frequency": {
          "type": "string"
        },
        "population": {
          "description": "Who the dose is for; drives the row stripe (adult grey, peds pink).",
          "type": "string",
          "enum": [
            "adult",
            "peds",
            "both"
          ],
          "default": "both"
        }
      },
      "required": [
        "drug",
        "dose",
        "route",
        "frequency"
      ],
      "additionalProperties": false
    },
    "branch_continuation": {
      "description": "Downstream chain under one branch (asymmetric flow).",
      "type": "object",
      "properties": {
        "entry_arrow_label": {
          "description": "Label on the arrow from the branch's last action into the first node, e.g. `Every 2 minutes`.",
          "type": "string"
        },
        "nodes": {
          "description": "Nodes rendered downward under this branch only.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/flow_node"
          }
        }
      },
      "required": [
        "nodes"
      ],
      "additionalProperties": false
    },
    "branch": {
      "description": "One branch of a severity flowchart.",
      "type": "object",
      "properties": {
        "id": {
          "description": "Branch id; the target of a convergence `loopback`.",
          "type": "string"
        },
        "label": {
          "description": "Branch header, e.g. `No Pulse`.",
          "type": "string"
        },
        "criteria": {
          "description": "Bullets under the label.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "actions": {
          "description": "Action tiles, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/action"
          }
        },
        "severity": {
          "description": "WHO IMCI tint: emergency = pink, priority = yellow, non_urgent = green.",
          "type": "string",
          "enum": [
            "none",
            "emergency",
            "priority",
            "non_urgent"
          ],
          "default": "none"
        },
        "continuation": {
          "$ref": "#/$defs/branch_continuation"
        },
        "continues": {
          "description": "Render label + down arrow only: the branch flows straight into the next block of the topic.",
          "type": "boolean",
          "default": false
        }
      },
      "required": [
        "id",
        "label"
      ],
      "additionalProperties": false
    },
    "linear_step": {
      "description": "A step in a linear flowchart: `type: content` = a titled box with bullets; otherwise an action tile (same fields as an action).",
      "type": "object",
      "properties": {
        "type": {
          "description": "Step form.",
          "type": "string",
          "enum": [
            "content",
            "action"
          ],
          "default": "action"
        }
      },
      "allOf": [
        {
          "if": {
            "properties": {
              "type": {
                "const": "content"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "type": "object",
            "properties": {
              "type": {
                "const": "content"
              },
              "title": {
                "description": "Box title, e.g. `Assess for:`.",
                "type": "string"
              },
              "bullets": {
                "description": "Bullets in the box.",
                "type": "array",
                "items": {
                  "type": "string"
                }
              }
            },
            "required": [
              "type",
              "title"
            ],
            "additionalProperties": false
          },
          "else": {
            "type": "object",
            "properties": {
              "type": {
                "const": "action"
              },
              "text": {
                "description": "Action text.",
                "type": "string"
              },
              "kind": {
                "description": "Action category (icon/styling).",
                "type": "string",
                "enum": [
                  "procedure",
                  "medication_administration",
                  "diagnostic",
                  "assessment",
                  "referral",
                  "communication"
                ],
                "default": "procedure"
              },
              "provider_level": {
                "description": "Minimum provider level cleared for the intervention (WVEMS badge): E = EMT, A = AEMT, I = Intermediate, P = Paramedic, P(CC) or CC = Critical Care. Omit for any level.",
                "type": "string",
                "enum": [
                  "E",
                  "A",
                  "I",
                  "P",
                  "P(CC)",
                  "CC"
                ]
              },
              "timing": {
                "type": "string"
              },
              "condition": {
                "type": "string"
              },
              "peds_only": {
                "description": "Pink `Peds` side tab.",
                "type": "boolean",
                "default": false
              }
            },
            "required": [
              "text"
            ],
            "additionalProperties": false
          }
        }
      ]
    },
    "differential_card": {
      "description": "One referential card in a differential grid.",
      "type": "object",
      "properties": {
        "title": {
          "description": "Card title, e.g. `Skull Fx`.",
          "type": "string"
        },
        "bullets": {
          "description": "Descriptive bullets.",
          "type": "array",
          "items": {
            "type": "string"
          }
        }
      },
      "required": [
        "title"
      ],
      "additionalProperties": false
    },
    "cascade_step": {
      "description": "One yes/no step of a cascade; `continuation` is the next step.",
      "type": "object",
      "properties": {
        "decision": {
          "description": "Yes/no question shown as the step header.",
          "type": "string"
        },
        "criteria": {
          "description": "Bullets under the question.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "action": {
          "$ref": "#/$defs/action"
        },
        "action_answer": {
          "description": "Which answer triggers `action`; the other answer continues.",
          "type": "string",
          "enum": [
            "yes",
            "no"
          ],
          "default": "yes"
        },
        "continuation": {
          "$ref": "#/$defs/cascade_step"
        }
      },
      "required": [
        "decision"
      ],
      "additionalProperties": false
    },
    "algo_table": {
      "description": "Compact bordered table rendered inside an algorithm box.",
      "type": "object",
      "properties": {
        "columns": {
          "description": "Column headers.",
          "type": "array",
          "items": {
            "type": [
              "string",
              "number"
            ]
          }
        },
        "rows": {
          "description": "Rows of cells.",
          "type": "array",
          "items": {
            "type": "array",
            "items": {
              "type": [
                "string",
                "number",
                "boolean"
              ]
            }
          }
        },
        "align": {
          "description": "Per-column alignment; default left for column 0, centre for the rest.",
          "type": "array",
          "items": {
            "type": "string",
            "enum": [
              "left",
              "center",
              "right"
            ]
          }
        }
      },
      "additionalProperties": false
    },
    "algo_box": {
      "description": "A content box: an outcome's result, a shared named box, or the terminal.",
      "type": "object",
      "properties": {
        "id": {
          "description": "Makes the box a `goto` target.",
          "type": "string"
        },
        "title": {
          "description": "Box title.",
          "type": "string"
        },
        "bullets": {
          "description": "Bullets under the title.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "severity": {
          "description": "WHO IMCI tint: emergency = pink, priority = yellow, non_urgent = green.",
          "type": "string",
          "enum": [
            "none",
            "emergency",
            "priority",
            "non_urgent"
          ],
          "default": "none"
        },
        "table": {
          "$ref": "#/$defs/algo_table"
        }
      },
      "additionalProperties": false,
      "minProperties": 1
    },
    "algo_outcome": {
      "description": "One labelled outcome of a decision stage.",
      "type": "object",
      "properties": {
        "label": {
          "description": "Outcome label on the arrow, e.g. `Yes`, `< 7 days`.",
          "type": "string"
        },
        "box": {
          "$ref": "#/$defs/algo_box"
        },
        "goto": {
          "description": "`id` of a shared box in `boxes` to jump to (instead of an inline `box`).",
          "type": "string"
        },
        "continue": {
          "description": "After this outcome the flow rejoins the spine and proceeds to the next stage; otherwise the outcome is a terminal leaf.",
          "type": "boolean",
          "default": false
        }
      },
      "required": [
        "label"
      ],
      "additionalProperties": false,
      "not": {
        "required": [
          "box",
          "goto"
        ]
      }
    },
    "algo_stage": {
      "description": "A decision stage on the vertical spine.",
      "type": "object",
      "properties": {
        "decision": {
          "description": "Decision prompt.",
          "type": "string"
        },
        "criteria": {
          "description": "Bullets under the prompt.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "outcomes": {
          "description": "Two or more labelled outcomes.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/algo_outcome"
          },
          "minItems": 1
        }
      },
      "required": [
        "decision",
        "outcomes"
      ],
      "additionalProperties": false
    },
    "cycle_branch": {
      "description": "A side box off a cycle node, optionally looping back.",
      "type": "object",
      "properties": {
        "label": {
          "description": "Arrow label from the node to this box.",
          "type": "string"
        },
        "side": {
          "description": "Which side of the spine the box sits on.",
          "type": "string",
          "enum": [
            "left",
            "right"
          ]
        },
        "box": {
          "$ref": "#/$defs/algo_box"
        },
        "loop_to": {
          "description": "`id` of a spine node to draw a return arrow to (the loop). Omit for a terminal side action.",
          "type": "string"
        },
        "loop_label": {
          "description": "Annotation on the return arrow, e.g. `reassess q5–10 min`.",
          "type": "string"
        }
      },
      "required": [
        "side",
        "box"
      ],
      "additionalProperties": false
    },
    "cycle_node": {
      "description": "One node on the spine of a cycle flowchart.",
      "type": "object",
      "properties": {
        "id": {
          "description": "Makes the node a `loop_to` target.",
          "type": "string"
        },
        "shape": {
          "description": "`box` = rectangle, `decision` = diamond.",
          "type": "string",
          "enum": [
            "box",
            "decision"
          ],
          "default": "box"
        },
        "title": {
          "description": "Node title.",
          "type": "string"
        },
        "bullets": {
          "description": "Bullets under the title.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "severity": {
          "description": "WHO IMCI tint: emergency = pink, priority = yellow, non_urgent = green.",
          "type": "string",
          "enum": [
            "none",
            "emergency",
            "priority",
            "non_urgent"
          ],
          "default": "none"
        },
        "branches": {
          "description": "Side boxes off this node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/cycle_branch"
          }
        },
        "down_label": {
          "description": "Label on the arrow to the next spine node, e.g. `once stable`.",
          "type": "string"
        }
      },
      "required": [
        "title"
      ],
      "additionalProperties": false
    },
    "flowchart_severity": {
      "description": "Entry → decision → parallel branches → convergence (the WVEMS/ProtocolBook default).",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "severity",
          "default": "severity"
        },
        "entry_chain": {
          "description": "Sequential nodes before the fork, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/flow_node"
          }
        },
        "entry": {
          "description": "Single entry node (shorthand for a one-node `entry_chain`; do not use both).",
          "$ref": "#/$defs/flow_node"
        },
        "pre_decision_actions": {
          "description": "Action tiles between the entry chain and the decision.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/action"
          }
        },
        "decision": {
          "description": "Optional explicit decision node before the branches.",
          "$ref": "#/$defs/flow_node"
        },
        "branches": {
          "description": "Parallel branches, left to right.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/branch"
          },
          "minItems": 1
        },
        "convergence": {
          "$ref": "#/$defs/convergence"
        },
        "post_convergence": {
          "description": "One more box below the convergence, reached by a forward exit arrow.",
          "$ref": "#/$defs/convergence"
        },
        "critical_care_link": {
          "$ref": "#/$defs/cc_link"
        },
        "dose_table": {
          "description": "Medication dose strip at the bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/dose_row"
          }
        },
        "warnings": {
          "description": "Side callouts flanking the first entry node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/warning"
          }
        }
      },
      "required": [
        "type",
        "branches"
      ],
      "additionalProperties": false,
      "not": {
        "required": [
          "entry",
          "entry_chain"
        ]
      }
    },
    "flowchart_linear": {
      "description": "Single column: entry → step → step → convergence. No decision, no branches.",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "linear"
        },
        "entry_chain": {
          "description": "Sequential nodes before the fork, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/flow_node"
          }
        },
        "entry": {
          "description": "Single entry node (shorthand for a one-node `entry_chain`; do not use both).",
          "$ref": "#/$defs/flow_node"
        },
        "steps": {
          "description": "Single-column steps, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/linear_step"
          },
          "minItems": 1
        },
        "convergence": {
          "$ref": "#/$defs/convergence"
        },
        "post_convergence": {
          "description": "One more box below the convergence, reached by a forward exit arrow.",
          "$ref": "#/$defs/convergence"
        },
        "critical_care_link": {
          "$ref": "#/$defs/cc_link"
        },
        "dose_table": {
          "description": "Medication dose strip at the bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/dose_row"
          }
        },
        "warnings": {
          "description": "Side callouts flanking the first entry node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/warning"
          }
        }
      },
      "required": [
        "type",
        "variant",
        "steps"
      ],
      "additionalProperties": false,
      "not": {
        "required": [
          "entry",
          "entry_chain"
        ]
      }
    },
    "flowchart_differential": {
      "description": "Decision into a grid of referential cards (no action tiles per card).",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "differential"
        },
        "entry_chain": {
          "description": "Sequential nodes before the fork, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/flow_node"
          }
        },
        "entry": {
          "description": "Single entry node (shorthand for a one-node `entry_chain`; do not use both).",
          "$ref": "#/$defs/flow_node"
        },
        "pre_decision_actions": {
          "description": "Action tiles between the entry chain and the decision.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/action"
          }
        },
        "decision": {
          "description": "Decision diamond above the card grid, e.g. `Location?`.",
          "$ref": "#/$defs/flow_node"
        },
        "cards": {
          "description": "Referential cards in a grid.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/differential_card"
          },
          "minItems": 1
        },
        "columns": {
          "description": "Grid column count.",
          "type": "integer",
          "minimum": 1,
          "default": 2
        },
        "convergence": {
          "$ref": "#/$defs/convergence"
        },
        "post_convergence": {
          "description": "One more box below the convergence, reached by a forward exit arrow.",
          "$ref": "#/$defs/convergence"
        },
        "critical_care_link": {
          "$ref": "#/$defs/cc_link"
        },
        "dose_table": {
          "description": "Medication dose strip at the bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/dose_row"
          }
        },
        "warnings": {
          "description": "Side callouts flanking the first entry node.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/warning"
          }
        }
      },
      "required": [
        "type",
        "variant",
        "cards"
      ],
      "additionalProperties": false,
      "not": {
        "required": [
          "entry",
          "entry_chain"
        ]
      }
    },
    "flowchart_cascade": {
      "description": "Linear yes/no chain (e.g. a contraindication checklist).",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "cascade"
        },
        "entry": {
          "$ref": "#/$defs/flow_node"
        },
        "root": {
          "$ref": "#/$defs/cascade_step"
        },
        "terminal_action": {
          "description": "Action taken if every step falls through.",
          "$ref": "#/$defs/action"
        },
        "action_width": {
          "description": "Fraction of the width given to the action column.",
          "type": "number",
          "minimum": 0,
          "maximum": 1,
          "default": 0.5
        }
      },
      "required": [
        "type",
        "variant",
        "entry",
        "root"
      ],
      "additionalProperties": false
    },
    "flowchart_algorithm": {
      "description": "Vertical multi-decision algorithm: stages with labelled outcomes; loops are `goto` references, not drawn arrows.",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "algorithm"
        },
        "entry": {
          "$ref": "#/$defs/flow_node"
        },
        "boxes": {
          "description": "Shared named boxes that outcomes `goto`.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/algo_box"
          }
        },
        "stages": {
          "description": "Decision stages down the spine.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/algo_stage"
          },
          "minItems": 1
        },
        "terminal": {
          "description": "Final box at the bottom of the spine.",
          "$ref": "#/$defs/algo_box"
        }
      },
      "required": [
        "type",
        "variant",
        "stages"
      ],
      "additionalProperties": false
    },
    "flowchart_cycle": {
      "description": "Cyclic algorithm: a spine whose side boxes can loop back to a node by `id` (drawn as a return arrow).",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        },
        "variant": {
          "const": "cycle"
        },
        "nodes": {
          "description": "Spine nodes, top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/cycle_node"
          },
          "minItems": 1
        }
      },
      "required": [
        "type",
        "variant",
        "nodes"
      ],
      "additionalProperties": false
    },
    "flowchart": {
      "description": "A flowchart in one of six variants, chosen by `variant` (default `severity`).",
      "type": "object",
      "properties": {
        "type": {
          "const": "flowchart"
        },
        "variant": {
          "description": "Flowchart variant.",
          "type": "string",
          "enum": [
            "severity",
            "cascade",
            "linear",
            "differential",
            "algorithm",
            "cycle"
          ],
          "default": "severity"
        }
      },
      "required": [
        "type"
      ],
      "allOf": [
        {
          "if": {
            "anyOf": [
              {
                "not": {
                  "required": [
                    "variant"
                  ]
                }
              },
              {
                "properties": {
                  "variant": {
                    "const": "severity"
                  }
                },
                "required": [
                  "variant"
                ]
              }
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_severity"
          }
        },
        {
          "if": {
            "properties": {
              "variant": {
                "const": "cascade"
              }
            },
            "required": [
              "variant"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_cascade"
          }
        },
        {
          "if": {
            "properties": {
              "variant": {
                "const": "linear"
              }
            },
            "required": [
              "variant"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_linear"
          }
        },
        {
          "if": {
            "properties": {
              "variant": {
                "const": "differential"
              }
            },
            "required": [
              "variant"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_differential"
          }
        },
        {
          "if": {
            "properties": {
              "variant": {
                "const": "algorithm"
              }
            },
            "required": [
              "variant"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_algorithm"
          }
        },
        {
          "if": {
            "properties": {
              "variant": {
                "const": "cycle"
              }
            },
            "required": [
              "variant"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart_cycle"
          }
        }
      ]
    },
    "table_cell": {
      "description": "A cell: a string (single line; a string containing newlines renders as markdown), a list of strings (bullets), or an object for span/markdown control.",
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        {
          "type": "object",
          "properties": {
            "text": {
              "description": "Cell text (markdown if multi-line).",
              "type": "string"
            },
            "span": {
              "description": "Number of columns this cell covers.",
              "type": "integer",
              "minimum": 1,
              "default": 1
            },
            "bullets": {
              "description": "Bullet list instead of `text`.",
              "type": "array",
              "items": {
                "type": "string"
              }
            }
          },
          "additionalProperties": false
        }
      ]
    },
    "table_row": {
      "description": "One table row.",
      "type": "object",
      "properties": {
        "cells": {
          "description": "Cells left to right; omit for a banner-only row.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/table_cell"
          }
        },
        "title": {
          "description": "Row banner rendered above the cells.",
          "type": "string"
        },
        "header": {
          "description": "Row label in a left header column.",
          "type": "string"
        },
        "group": {
          "description": "Group label; contiguous rows with the same group collapse under one label.",
          "type": "string"
        },
        "severity": {
          "description": "WHO IMCI tint: emergency = pink, priority = yellow, non_urgent = green.",
          "type": "string",
          "enum": [
            "none",
            "emergency",
            "priority",
            "non_urgent"
          ],
          "default": "none"
        }
      },
      "additionalProperties": false,
      "minProperties": 1
    },
    "table": {
      "description": "Columns + rows with optional severity tinting.",
      "type": "object",
      "properties": {
        "type": {
          "const": "table"
        },
        "title": {
          "description": "Block title above the table.",
          "type": "string"
        },
        "columns": {
          "description": "Column headers; empty list = no header row.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "column_flex": {
          "description": "Per-column width weights (one per column).",
          "type": "array",
          "items": {
            "type": "integer",
            "minimum": 1
          }
        },
        "column_widths": {
          "description": "Per-column fixed widths in px, for `layout: scroll`.",
          "type": "array",
          "items": {
            "type": "number",
            "minimum": 1
          }
        },
        "column_align": {
          "description": "Per-column text alignment.",
          "type": "array",
          "items": {
            "type": "string",
            "enum": [
              "left",
              "right",
              "center"
            ]
          }
        },
        "column_tint": {
          "description": "Per-column background tint; empty string = none.",
          "type": "array",
          "items": {
            "anyOf": [
              {
                "$ref": "#/$defs/color"
              },
              {
                "type": "string",
                "maxLength": 0
              }
            ]
          }
        },
        "column_bar": {
          "description": "Per-column in-cell magnitude bars for numeric cells.",
          "type": "array",
          "items": {
            "type": "boolean"
          }
        },
        "zebra": {
          "description": "Alternate row shading (where a row has no severity tint).",
          "type": "boolean",
          "default": false
        },
        "sticky_header": {
          "description": "Pin the header row while the body scrolls (scroll layout).",
          "type": "boolean",
          "default": false
        },
        "sticky_first_column": {
          "description": "Pin the first column while the body scrolls horizontally (scroll layout).",
          "type": "boolean",
          "default": false
        },
        "lookup": {
          "description": "Show a go-to-row finder keyed on the first column.",
          "type": "boolean",
          "default": false
        },
        "lookup_label": {
          "description": "Label for the finder field; default `Go to <first column>`.",
          "type": "string"
        },
        "max_height": {
          "description": "Max height in px; the table scrolls inside it.",
          "type": "number",
          "minimum": 1
        },
        "rows": {
          "description": "Data rows.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/table_row"
          },
          "minItems": 1
        },
        "layout": {
          "description": "`standard` = dense grid; `boxed` = each cell a rounded tile (flow-grid rows); `scroll` = fixed column widths, horizontal scroll.",
          "type": "string",
          "enum": [
            "standard",
            "boxed",
            "scroll"
          ],
          "default": "standard"
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "rows"
      ],
      "additionalProperties": false
    },
    "prose": {
      "description": "Markdown text. Most content lives here.",
      "type": "object",
      "properties": {
        "type": {
          "const": "prose"
        },
        "markdown": {
          "description": "Markdown: `**bold**`, `- ` bullets, and links `[text](topic:<id>)`, `[text](topic:<id>#<anchor>)`, `[text](#<anchor>)` or an https URL. Provider badges `{E}` `{A}` `{I}` `{P}` `{P(CC)}` `{}`.",
          "type": "string"
        },
        "title": {
          "description": "Bold sub-header above the text.",
          "type": "string"
        },
        "highlight": {
          "description": "Tinted (paediatrics pink) container.",
          "type": "boolean",
          "default": false
        },
        "callout": {
          "description": "Attention card (amber by default) with the title as a chip.",
          "type": "boolean",
          "default": false
        },
        "dashed": {
          "description": "Dashed outline for a `callout` (the print's conditional box).",
          "type": "boolean",
          "default": false
        },
        "boxed": {
          "description": "Rounded-border centred tile, for use as a grid cell in a `row`.",
          "type": "boolean",
          "default": false
        },
        "text_scale": {
          "description": "Body size as a fraction of the normal prose size (e.g. 0.8 for references).",
          "type": "number",
          "exclusiveMinimum": 0,
          "default": 1.0
        },
        "call_er": {
          "description": "Pair this box with the print's `Call ER` tile on its right.",
          "type": "boolean",
          "default": false
        },
        "critical_care_link": {
          "description": "Lavender Critical-Care tab fused under this box (WVEMS).",
          "$ref": "#/$defs/cc_link"
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "markdown"
      ],
      "additionalProperties": false
    },
    "band_callout": {
      "description": "Markdown tinted to say who it applies to (WVEMS population/credential bands).",
      "type": "object",
      "properties": {
        "type": {
          "const": "band_callout"
        },
        "band": {
          "description": "`peds` = pink Pediatrics band; `critical_care` = lavender Critical Care band.",
          "type": "string",
          "enum": [
            "peds",
            "pediatrics",
            "critical_care",
            "cc"
          ]
        },
        "markdown": {
          "description": "Markdown: `**bold**`, `- ` bullets, and links `[text](topic:<id>)`, `[text](topic:<id>#<anchor>)`, `[text](#<anchor>)` or an https URL. Provider badges `{E}` `{A}` `{I}` `{P}` `{P(CC)}` `{}`.",
          "type": "string"
        },
        "title": {
          "description": "Section label inside the band; omit for the band's default (`Pediatrics` / `Critical Care`); empty string for a bare band.",
          "type": "string"
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "band",
        "markdown"
      ],
      "additionalProperties": false
    },
    "drug_dose": {
      "description": "One dose line of a drug card.",
      "type": "object",
      "properties": {
        "text": {
          "description": "Dose line.",
          "type": "string"
        },
        "population": {
          "description": "Who the dose is for; drives the row stripe (adult grey, peds pink).",
          "type": "string",
          "enum": [
            "adult",
            "peds",
            "both"
          ],
          "default": "both"
        }
      },
      "required": [
        "text"
      ],
      "additionalProperties": false
    },
    "drug_card": {
      "description": "Canonical drug reference card.",
      "type": "object",
      "properties": {
        "type": {
          "const": "drug_card"
        },
        "name": {
          "description": "Drug name; also its default anchor slug.",
          "type": "string"
        },
        "class": {
          "description": "Drug class.",
          "type": "string"
        },
        "indications": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "contraindications": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "doses": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/drug_dose"
          }
        },
        "warnings": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "pearls": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "image": {
          "description": "Asset path of a product shot, e.g. `assets/books/<book>/images/x.png`.",
          "type": "string"
        },
        "critical_care": {
          "description": "Critical-Care restricted (lavender notes zone).",
          "type": "boolean",
          "default": false
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "name"
      ],
      "additionalProperties": false
    },
    "procedure_card": {
      "description": "How-to procedure card: scope-badged header over numbered steps.",
      "type": "object",
      "properties": {
        "type": {
          "const": "procedure_card"
        },
        "name": {
          "description": "Procedure name; also its default anchor slug.",
          "type": "string"
        },
        "scope": {
          "description": "Minimum provider level cleared for the intervention (WVEMS badge): E = EMT, A = AEMT, I = Intermediate, P = Paramedic, P(CC) or CC = Critical Care. Omit for any level.",
          "type": "string",
          "enum": [
            "E",
            "A",
            "I",
            "P",
            "P(CC)",
            "CC"
          ]
        },
        "steps": {
          "description": "Step lines. Prefix syntax: plain = next numbered step; `@2a text` = explicit label; `- text` = sub-bullet; `~[E] text` = scope note; `[E]` on a step = inline scope chip; leading `:` = dashed emphasis; leading `!` = pink peds band; leading `^` = lavender Critical-Care band; `NOTE: text` = full-width note.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "image": {
          "description": "Asset path of an illustration.",
          "type": "string"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "name"
      ],
      "additionalProperties": false
    },
    "image": {
      "description": "Figure with caption.",
      "type": "object",
      "properties": {
        "type": {
          "const": "image"
        },
        "path": {
          "description": "Asset path, e.g. `assets/books/<book>/images/figure.png`.",
          "type": "string"
        },
        "caption": {
          "type": "string"
        },
        "size": {
          "description": "Rendered width.",
          "type": "string",
          "enum": [
            "small",
            "medium",
            "large",
            "full"
          ],
          "default": "medium"
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "path"
      ],
      "additionalProperties": false
    },
    "row": {
      "description": "Horizontal layout of child blocks.",
      "type": "object",
      "properties": {
        "type": {
          "const": "row"
        },
        "blocks": {
          "description": "Children side by side; their `flex` values should sum to 12.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/block"
          },
          "minItems": 1
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        }
      },
      "required": [
        "type",
        "blocks"
      ],
      "additionalProperties": false
    },
    "column": {
      "description": "Vertical layout of child blocks (inside a `row` slot).",
      "type": "object",
      "properties": {
        "type": {
          "const": "column"
        },
        "blocks": {
          "description": "Children stacked vertically; an empty list is a blank spacer cell.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/block"
          }
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        }
      },
      "required": [
        "type",
        "blocks"
      ],
      "additionalProperties": false
    },
    "arrows": {
      "description": "Down or right arrows bridging rows of a flow grid.",
      "type": "object",
      "properties": {
        "type": {
          "const": "arrows"
        },
        "count": {
          "description": "Number of evenly spaced arrows.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        },
        "label": {
          "description": "Label on the arrows.",
          "type": "string"
        },
        "length": {
          "description": "Arrow length in px.",
          "type": "number",
          "minimum": 1,
          "default": 14
        },
        "direction": {
          "description": "Arrow direction (`right` requires count 1).",
          "type": "string",
          "enum": [
            "down",
            "right"
          ],
          "default": "down"
        },
        "inline": {
          "description": "Label beside the arrow instead of above it.",
          "type": "boolean",
          "default": false
        },
        "flex": {
          "description": "Share of the parent row/column width (12-column convention: a row's children should sum to 12). Only meaningful inside a `row` or `column`.",
          "type": "integer",
          "minimum": 1,
          "default": 1
        }
      },
      "required": [
        "type"
      ],
      "additionalProperties": false
    },
    "merge_arrows": {
      "description": "Several arrows converging into one.",
      "type": "object",
      "properties": {
        "type": {
          "const": "merge_arrows"
        },
        "columns": {
          "description": "Grid width this block spans.",
          "type": "integer",
          "minimum": 1
        },
        "sources": {
          "description": "Column indices of the top arrows.",
          "type": "array",
          "items": {
            "type": "integer",
            "minimum": 0
          }
        },
        "target_center": {
          "description": "Column index (fractional allowed) of the merged arrow.",
          "type": "number",
          "minimum": 0
        }
      },
      "required": [
        "type",
        "columns",
        "sources",
        "target_center"
      ],
      "additionalProperties": false
    },
    "conversion_dose": {
      "description": "A discrete strength tagged with its tier (tiers mode).",
      "type": "object",
      "properties": {
        "dose": {
          "type": [
            "string",
            "number"
          ],
          "description": "Manufactured strength."
        },
        "tier": {
          "description": "Tier name from `tiers`.",
          "type": "string"
        }
      },
      "required": [
        "dose",
        "tier"
      ],
      "additionalProperties": false
    },
    "conversion_agent": {
      "description": "One agent in a conversion.",
      "type": "object",
      "properties": {
        "name": {
          "description": "Agent name.",
          "type": "string"
        },
        "route": {
          "description": "Route, when the same agent has several (e.g. `PO`, `IV`).",
          "type": "string"
        },
        "factor": {
          "description": "Multiplier to the reference (equivalence mode).",
          "type": "number"
        },
        "unit": {
          "description": "Dose unit override for this agent.",
          "type": "string"
        },
        "doses": {
          "description": "Strengths (tiers mode).",
          "type": "array",
          "items": {
            "$ref": "#/$defs/conversion_dose"
          }
        }
      },
      "required": [
        "name"
      ],
      "additionalProperties": false
    },
    "conversion": {
      "description": "Interactive dose converter.",
      "type": "object",
      "properties": {
        "type": {
          "const": "conversion"
        },
        "mode": {
          "description": "`equivalence` = free numeric entry with factors to a reference; `tiers` = pick from fixed strengths grouped in tiers.",
          "type": "string",
          "enum": [
            "equivalence",
            "tiers"
          ],
          "default": "equivalence"
        },
        "title": {
          "type": "string"
        },
        "reference": {
          "description": "Reference anchor name (equivalence), e.g. `oral morphine`.",
          "type": "string"
        },
        "reference_label": {
          "description": "Short label for the reference line, e.g. `MME`.",
          "type": "string"
        },
        "unit": {
          "description": "Default dose unit.",
          "type": "string"
        },
        "source": {
          "description": "Where the factors/tiers come from (shown; required for clinical safety).",
          "type": "string"
        },
        "tiers": {
          "description": "Ordered tier names low → high (tiers mode).",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "tier_note": {
          "type": "string"
        },
        "agents": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/conversion_agent"
          },
          "minItems": 1
        },
        "excluded": {
          "description": "Agents deliberately not auto-converted, with the reason.",
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "name": {
                "type": "string"
              },
              "reason": {
                "type": "string"
              }
            },
            "required": [
              "name",
              "reason"
            ],
            "additionalProperties": false
          }
        },
        "caveats": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "mode",
        "agents"
      ],
      "additionalProperties": false
    },
    "formula_option": {
      "description": "A select option: a bare value, or `{value, label}`.",
      "anyOf": [
        {
          "type": [
            "string",
            "number",
            "boolean"
          ]
        },
        {
          "type": "object",
          "properties": {
            "value": {
              "type": [
                "string",
                "number",
                "boolean"
              ]
            },
            "label": {
              "type": "string"
            }
          },
          "required": [
            "value"
          ],
          "additionalProperties": false
        }
      ]
    },
    "formula_input": {
      "description": "One input field of a formula calculator.",
      "type": "object",
      "properties": {
        "key": {
          "description": "Value key the formula reads.",
          "type": "string"
        },
        "label": {
          "description": "Field label.",
          "type": "string"
        },
        "type": {
          "description": "Field type.",
          "type": "string",
          "enum": [
            "number",
            "select",
            "boolean"
          ],
          "default": "number"
        },
        "unit": {
          "type": "string"
        },
        "help": {
          "type": "string"
        },
        "default": {
          "type": [
            "string",
            "number",
            "boolean"
          ],
          "description": "Initial value."
        },
        "options": {
          "description": "Options for a `select` input.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/formula_option"
          }
        },
        "optional": {
          "description": "Does not block computation when blank.",
          "type": "boolean",
          "default": false
        }
      },
      "required": [
        "key",
        "label"
      ],
      "additionalProperties": false
    },
    "formula": {
      "description": "Numbers in → number out, via a built-in formula.",
      "type": "object",
      "properties": {
        "type": {
          "const": "formula"
        },
        "kind": {
          "description": "Which built-in formula computes the result. The math is compiled into the app; a YAML author cannot add kinds.",
          "type": "string",
          "enum": [
            "renal_function",
            "map",
            "corrected_sodium",
            "anion_gap",
            "aa_gradient",
            "winters",
            "ideal_body_weight",
            "holliday_segar",
            "meld3",
            "qtc",
            "free_water_deficit",
            "anthropometrics",
            "osmolal_gap",
            "parkland",
            "urinary_indices",
            "anc",
            "reticulocyte",
            "lights",
            "fib4",
            "maddrey",
            "oxygenation",
            "dday_age",
            "lille",
            "prevent_ascvd",
            "glasgow_blatchford",
            "adrogue_madias",
            "hba1c_eag"
          ]
        },
        "title": {
          "type": "string"
        },
        "source": {
          "description": "Provenance of the formula (shown).",
          "type": "string"
        },
        "inputs": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/formula_input"
          },
          "minItems": 1
        },
        "notes": {
          "description": "Lines shown under the result.",
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "caveats": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "kind",
        "inputs"
      ],
      "additionalProperties": false
    },
    "score_option": {
      "description": "One option of a choice/scale item.",
      "type": "object",
      "properties": {
        "value": {
          "type": [
            "string",
            "number",
            "boolean"
          ]
        },
        "label": {
          "description": "Defaults to the value.",
          "type": "string"
        },
        "points": {
          "type": "number",
          "default": 0
        }
      },
      "required": [
        "value"
      ],
      "additionalProperties": false
    },
    "score_item": {
      "description": "One scored criterion.",
      "type": "object",
      "properties": {
        "key": {
          "type": "string"
        },
        "label": {
          "type": "string"
        },
        "type": {
          "description": "`toggle` = yes/no worth `points`; `choice` = pick one option (chips); `scale` = pick one level (stepper).",
          "type": "string",
          "enum": [
            "toggle",
            "choice",
            "scale"
          ],
          "default": "toggle"
        },
        "help": {
          "type": "string"
        },
        "points": {
          "description": "Points when a toggle is on.",
          "type": "number",
          "default": 0
        },
        "options": {
          "description": "Options for choice/scale.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/score_option"
          }
        },
        "default": {
          "type": [
            "string",
            "number",
            "boolean"
          ],
          "description": "Initially selected option value."
        }
      },
      "required": [
        "key",
        "label"
      ],
      "additionalProperties": false
    },
    "score_band": {
      "description": "A total-score interval and its interpretation.",
      "type": "object",
      "properties": {
        "min": {
          "type": "number",
          "default": 0
        },
        "max": {
          "description": "Omit for open-ended.",
          "type": "number"
        },
        "label": {
          "type": "string"
        },
        "detail": {
          "type": "string"
        },
        "severity": {
          "description": "Result tint.",
          "type": "string",
          "enum": [
            "none",
            "info",
            "warn",
            "alert"
          ],
          "default": "none"
        }
      },
      "required": [
        "label"
      ],
      "additionalProperties": false
    },
    "score": {
      "description": "Criteria → summed points → risk band.",
      "type": "object",
      "properties": {
        "type": {
          "const": "score"
        },
        "title": {
          "type": "string"
        },
        "unit": {
          "type": "string",
          "default": "points"
        },
        "show_total": {
          "description": "Show the summed total above the band (default true). Set false when the points encode a decision tree rather than a meaningful sum (e.g. PECARN), so only the band is shown.",
          "type": "boolean",
          "default": true
        },
        "source": {
          "description": "Provenance of the score (shown).",
          "type": "string"
        },
        "items": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/score_item"
          },
          "minItems": 1
        },
        "bands": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/score_band"
          },
          "minItems": 1
        },
        "notes": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "caveats": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "anchor": {
          "description": "Slug that makes this block a link target: `[text](#slug)` in this topic, or `topic:<id>#slug` from another topic.",
          "type": "string"
        },
        "palette": {
          "$ref": "#/$defs/palette"
        }
      },
      "required": [
        "type",
        "items",
        "bands"
      ],
      "additionalProperties": false
    },
    "block": {
      "description": "One vertical section of a page, chosen by `type`.",
      "type": "object",
      "properties": {
        "type": {
          "description": "Block type.",
          "type": "string",
          "enum": [
            "prose",
            "band_callout",
            "flowchart",
            "table",
            "drug_card",
            "procedure_card",
            "image",
            "row",
            "column",
            "arrows",
            "merge_arrows",
            "conversion",
            "formula",
            "score"
          ]
        }
      },
      "required": [
        "type"
      ],
      "allOf": [
        {
          "if": {
            "properties": {
              "type": {
                "const": "prose"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/prose"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "band_callout"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/band_callout"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "flowchart"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/flowchart"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "table"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/table"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "drug_card"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/drug_card"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "procedure_card"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/procedure_card"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "image"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/image"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "row"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/row"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "column"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/column"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "arrows"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/arrows"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "merge_arrows"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/merge_arrows"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "conversion"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/conversion"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "formula"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/formula"
          }
        },
        {
          "if": {
            "properties": {
              "type": {
                "const": "score"
              }
            },
            "required": [
              "type"
            ]
          },
          "then": {
            "$ref": "#/$defs/score"
          }
        }
      ]
    },
    "page": {
      "description": "One page of a topic (maps to one source page).",
      "type": "object",
      "properties": {
        "page_number": {
          "description": "Printed page number of the source; shown in the header badge and page-break divider.",
          "type": "integer"
        },
        "blocks": {
          "description": "Blocks top to bottom.",
          "type": "array",
          "items": {
            "$ref": "#/$defs/block"
          },
          "minItems": 1
        }
      },
      "required": [
        "blocks"
      ],
      "additionalProperties": false
    }
  }
}