{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://mif-spec.dev/schema/mif.schema.json",
  "title": "MIF — Modeled Information Format (v1.0)",
  "description": "JSON Schema for validating the derived JSON-LD projection of a MIF v1.0 concept",
  "type": "object",
  "required": ["@context", "@type", "@id", "content", "created"],
  "anyOf": [
    { "required": ["conceptType"] },
    { "required": ["memoryType"] }
  ],
  "properties": {
    "@context": {
      "description": "JSON-LD context",
      "oneOf": [
        { "type": "string", "format": "uri" },
        { "type": "array", "items": { "type": ["string", "object"] } },
        { "type": "object" }
      ]
    },
    "@type": {
      "description": "Type of the concept document",
      "oneOf": [
        { "const": "Concept" },
        { "const": "Memory" },
        { "type": "array", "contains": { "const": "Concept" } }
      ]
    },
    "@id": {
      "type": "string",
      "pattern": "^urn:mif:",
      "description": "Unique identifier in URN format"
    },
    "conceptType": {
      "type": "string",
      "enum": ["semantic", "episodic", "procedural"],
      "description": "Knowledge taxonomy: semantic (declarative knowledge), episodic (time-bound records), procedural (how-to knowledge)"
    },
    "memoryType": {
      "type": "string",
      "enum": ["semantic", "episodic", "procedural"],
      "description": "Deprecated v0.1 alias for conceptType; retained for backward compatibility"
    },
    "timestamp": {
      "type": "string",
      "format": "date-time",
      "description": "OKF-recommended mirror of modified (or created)"
    },
    "description": {
      "type": "string",
      "description": "OKF-recommended description, mapped from MIF summary"
    },
    "content": {
      "type": "string",
      "minLength": 1,
      "description": "The memory content in Markdown format"
    },
    "title": {
      "type": "string",
      "description": "Human-readable title"
    },
    "created": {
      "type": "string",
      "format": "date-time",
      "description": "Creation timestamp (ISO 8601)"
    },
    "modified": {
      "type": "string",
      "format": "date-time",
      "description": "Last modification timestamp (ISO 8601)"
    },
    "ontology": {
      "$ref": "#/$defs/OntologyReference",
      "description": "Reference to the ontology this memory conforms to"
    },
    "entity": {
      "$ref": "#/$defs/EntityData",
      "description": "Structured entity data for ontology-typed memories"
    },
    "namespace": {
      "type": "string",
      "pattern": "^[a-zA-Z0-9_-]+(/[a-zA-Z0-9_-]+)*$",
      "description": "Hierarchical namespace path"
    },
    "tags": {
      "type": "array",
      "items": { "type": "string" },
      "description": "Classification tags"
    },
    "aliases": {
      "type": "array",
      "items": { "type": "string" },
      "description": "Alternative names for the memory"
    },
    "entities": {
      "type": "array",
      "items": { "$ref": "#/$defs/EntityReference" },
      "description": "Referenced entities"
    },
    "relationships": {
      "type": "array",
      "items": { "$ref": "#/$defs/Relationship" },
      "description": "Typed relationships to other memories"
    },
    "temporal": {
      "$ref": "#/$defs/TemporalMetadata",
      "description": "Temporal validity and decay data"
    },
    "provenance": {
      "$ref": "#/$defs/Provenance",
      "description": "Source and trust data"
    },
    "embedding": {
      "$ref": "#/$defs/EmbeddingReference",
      "description": "Embedding model reference"
    },
    "citations": {
      "type": "array",
      "items": { "$ref": "#/$defs/Citation" },
      "description": "Citation references (Level 3)"
    },
    "documents": {
      "type": "array",
      "items": { "$ref": "#/$defs/DocumentReference" },
      "description": "Source documents that travel alongside this memory by reference (not embedded). Vendor-neutral pointers to the underlying artifacts a memory was derived from."
    },
    "summary": {
      "type": "string",
      "maxLength": 500,
      "description": "Compressed content summary (Level 3, max 500 chars)"
    },
    "properties": {
      "type": "object",
      "additionalProperties": {
        "type": ["string", "number", "boolean", "null"]
      },
      "description": "First-class scalar properties: literal key/value pairs (e.g. from a knowledge-graph literal-object triple) that have no concept target and therefore cannot be a relationship. Values MUST be scalar (string, number, boolean, or null); nested objects/arrays are out of scope at Level 1."
    },
    "compressedAt": {
      "type": "string",
      "format": "date-time",
      "description": "When compression was applied (Level 3)"
    },
    "extensions": {
      "type": "object",
      "additionalProperties": true,
      "description": "Provider-specific extensions"
    }
  },
  "$defs": {
    "DocumentReference": {
      "type": "object",
      "description": "Vendor-neutral reference to a source document that travels alongside a memory by reference rather than by embedding a vendor-specific document schema. Locate the document by either `url` or `id`.",
      "required": ["@type"],
      "anyOf": [
        { "required": ["url"] },
        { "required": ["id"] }
      ],
      "properties": {
        "@type": {
          "const": "DocumentReference"
        },
        "id": {
          "type": "string",
          "minLength": 1,
          "description": "Stable identifier for the document (e.g. a URN or opaque key) when no resolvable URL is available"
        },
        "documentType": {
          "type": "string",
          "description": "Document category",
          "oneOf": [
            {
              "enum": [
                "pdf",
                "html",
                "markdown",
                "text",
                "transcript",
                "dataset",
                "spreadsheet",
                "presentation",
                "image",
                "audio",
                "video",
                "email",
                "other"
              ]
            },
            {
              "type": "string",
              "pattern": "^[a-zA-Z][a-zA-Z0-9]*:[a-zA-Z][a-zA-Z0-9-]*$",
              "description": "Custom namespaced type"
            }
          ]
        },
        "url": {
          "type": "string",
          "format": "uri",
          "minLength": 1,
          "description": "Resolvable location of the document"
        },
        "hash": {
          "type": "object",
          "description": "Content hash for integrity verification",
          "required": ["algorithm", "value"],
          "properties": {
            "algorithm": {
              "type": "string",
              "minLength": 1,
              "description": "Hash algorithm (e.g. sha256, sha512, blake3)"
            },
            "value": {
              "type": "string",
              "minLength": 1,
              "description": "Hash digest value"
            }
          },
          "additionalProperties": false
        },
        "contentType": {
          "type": "string",
          "minLength": 1,
          "description": "Media type of the document (e.g. application/pdf, text/html)"
        },
        "byteLength": {
          "type": "integer",
          "minimum": 0,
          "description": "Size of the document in bytes"
        },
        "version": {
          "type": "string",
          "minLength": 1,
          "description": "Version token for the document (e.g. a commit SHA, ETag, or revision label)"
        },
        "retrievedAt": {
          "type": "string",
          "format": "date-time",
          "description": "When the document was retrieved (ISO 8601)"
        },
        "title": {
          "type": "string",
          "minLength": 1,
          "description": "Human-readable document title"
        }
      },
      "additionalProperties": false
    },
    "Citation": {
      "type": "object",
      "required": ["@type", "citationType", "citationRole", "title", "url"],
      "properties": {
        "@type": {
          "const": "Citation"
        },
        "citationType": {
          "type": "string",
          "description": "Source category",
          "oneOf": [
            {
              "enum": [
                "article",
                "book",
                "paper",
                "website",
                "documentation",
                "repository",
                "video",
                "podcast",
                "specification",
                "dataset",
                "tool",
                "other"
              ]
            },
            {
              "type": "string",
              "pattern": "^[a-zA-Z][a-zA-Z0-9]*:[a-zA-Z][a-zA-Z0-9-]*$",
              "description": "Custom namespaced type"
            }
          ]
        },
        "citationRole": {
          "type": "string",
          "description": "Relationship to memory",
          "oneOf": [
            {
              "enum": [
                "supports",
                "refutes",
                "background",
                "methodology",
                "contradicts",
                "extends",
                "derived",
                "source",
                "example",
                "review"
              ]
            },
            {
              "type": "string",
              "pattern": "^[a-zA-Z][a-zA-Z0-9]*:[a-zA-Z][a-zA-Z0-9-]*$",
              "description": "Custom namespaced role"
            }
          ]
        },
        "title": {
          "type": "string",
          "minLength": 1,
          "description": "Citation title"
        },
        "url": {
          "type": "string",
          "format": "uri",
          "description": "Citation URL"
        },
        "author": {
          "description": "Author(s) as entity reference(s) or plain text",
          "oneOf": [
            { "$ref": "#/$defs/EntityReference" },
            {
              "type": "array",
              "items": { "$ref": "#/$defs/EntityReference" }
            },
            { "type": "string" }
          ]
        },
        "date": {
          "type": "string",
          "format": "date",
          "description": "Publication date (ISO 8601)"
        },
        "accessed": {
          "type": "string",
          "format": "date",
          "description": "Access date (ISO 8601)"
        },
        "relevance": {
          "type": "number",
          "minimum": 0,
          "maximum": 1,
          "description": "Relevance score (0.0-1.0)"
        },
        "note": {
          "type": "string",
          "maxLength": 1000,
          "description": "Free-form annotation"
        }
      },
      "additionalProperties": false
    },
    "EntityReference": {
      "$ref": "./definitions/entity-reference.schema.json"
    },
    "Relationship": {
      "type": "object",
      "description": "v1.0 typed relationship: authoritative in frontmatter, mirrored as an OKF-legible body markdown link (SPECIFICATION.md 4.4)",
      "required": ["type", "target"],
      "properties": {
        "type": {
          "type": "string",
          "description": "Relationship type as a kebab-case token (e.g. derived-from, supersedes, relates-to) or a custom namespaced type",
          "pattern": "^[a-z0-9][a-z0-9-]*(:[a-z0-9][a-z0-9-]*)?$"
        },
        "target": {
          "type": "string",
          "description": "Bundle-relative path to the target concept (e.g. /semantic/policy.md) or a urn:mif: identifier"
        },
        "strength": {
          "type": "number",
          "minimum": 0,
          "maximum": 1,
          "description": "Relationship strength"
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        }
      },
      "additionalProperties": false
    },
    "TemporalMetadata": {
      "type": "object",
      "properties": {
        "@type": {
          "const": "TemporalMetadata"
        },
        "validFrom": {
          "type": ["string", "null"],
          "format": "date-time"
        },
        "validUntil": {
          "type": ["string", "null"],
          "format": "date-time"
        },
        "recordedAt": {
          "type": "string",
          "format": "date-time"
        },
        "ttl": {
          "type": "string",
          "pattern": "^P",
          "description": "ISO 8601 duration"
        },
        "decay": {
          "type": "object",
          "properties": {
            "model": {
              "type": "string",
              "enum": ["none", "linear", "exponential", "step"]
            },
            "halfLife": {
              "type": "string",
              "pattern": "^P"
            },
            "currentStrength": {
              "type": "number",
              "minimum": 0,
              "maximum": 1
            },
            "strength": {
              "type": "number",
              "minimum": 0,
              "maximum": 1,
              "description": "Alias for currentStrength"
            },
            "lastReinforced": {
              "type": "string",
              "format": "date-time",
              "description": "When the memory was last reinforced"
            }
          },
          "additionalProperties": false
        },
        "accessCount": {
          "type": "integer",
          "minimum": 0
        },
        "lastAccessed": {
          "type": "string",
          "format": "date-time"
        },
        "reinforcementHistory": {
          "type": "array",
          "items": {
            "type": "object",
            "required": ["timestamp", "event"],
            "properties": {
              "timestamp": {
                "type": "string",
                "format": "date-time"
              },
              "event": {
                "type": "string"
              },
              "strengthDelta": {
                "type": "number"
              },
              "context": {
                "type": "string"
              }
            },
            "additionalProperties": false
          },
          "description": "History of reinforcement events that strengthened or weakened the memory"
        }
      },
      "additionalProperties": false
    },
    "Provenance": {
      "type": "object",
      "properties": {
        "@type": {
          "type": "string"
        },
        "sourceType": {
          "type": "string",
          "enum": [
            "user_explicit",
            "user_implicit",
            "agent_inferred",
            "external_import",
            "system_generated"
          ]
        },
        "confidence": {
          "type": "number",
          "minimum": 0,
          "maximum": 1
        },
        "trustLevel": {
          "type": "string",
          "enum": [
            "verified",
            "user_stated",
            "high_confidence",
            "moderate_confidence",
            "low_confidence",
            "uncertain"
          ]
        },
        "sourceRef": {
          "type": "string",
          "description": "OPTIONAL reference to the originating source (e.g. conversation:conv-456)"
        },
        "agent": {
          "type": "string",
          "description": "OPTIONAL identifier of the agent that created the unit (e.g. claude-3-opus)"
        },
        "agentVersion": {
          "type": "string",
          "description": "OPTIONAL version of the creating agent"
        },
        "wasGeneratedBy": {
          "$ref": "#/$defs/ProvNode",
          "description": "OPTIONAL prov:wasGeneratedBy — the activity that produced this unit"
        },
        "wasAttributedTo": {
          "$ref": "#/$defs/ProvNode",
          "description": "OPTIONAL prov:wasAttributedTo — the agent the unit is attributed to"
        },
        "wasDerivedFrom": {
          "description": "OPTIONAL prov:wasDerivedFrom — the entity or entities this unit was derived from",
          "oneOf": [
            { "$ref": "#/$defs/ProvNode" },
            { "type": "array", "items": { "$ref": "#/$defs/ProvNode" } }
          ]
        }
      },
      "additionalProperties": true
    },
    "ProvNode": {
      "description": "A W3C-PROV node: either a plain IRI/identifier string or an open node object (e.g. {\"@id\": \"...\", \"@type\": \"prov:Activity\"}). Kept permissive because PROV graphs are open-ended.",
      "oneOf": [
        { "type": "string" },
        {
          "type": "object",
          "anyOf": [
            { "required": ["@id"] },
            { "required": ["id"] }
          ],
          "additionalProperties": true
        }
      ]
    },
    "EmbeddingReference": {
      "type": "object",
      "properties": {
        "@type": {
          "const": "EmbeddingReference"
        },
        "model": {
          "type": "string"
        },
        "modelVersion": {
          "type": "string"
        },
        "dimensions": {
          "type": "integer",
          "minimum": 1
        },
        "sourceText": {
          "type": "string"
        },
        "vectorUri": {
          "type": "string",
          "format": "uri"
        },
        "normalized": {
          "type": "boolean"
        }
      },
      "additionalProperties": false
    },
    "OntologyReference": {
      "type": "object",
      "description": "Reference to the ontology this memory conforms to",
      "required": ["id"],
      "properties": {
        "@type": {
          "const": "OntologyReference"
        },
        "id": {
          "type": "string",
          "pattern": "^[a-z][a-z0-9-]*$",
          "description": "Ontology identifier (must match ontology.id in ontology definition)"
        },
        "version": {
          "type": "string",
          "pattern": "^\\d+\\.\\d+\\.\\d+.*$",
          "description": "Semantic version of the ontology"
        },
        "uri": {
          "type": "string",
          "format": "uri",
          "description": "URI to the ontology definition"
        }
      },
      "additionalProperties": false
    },
    "EntityData": {
      "type": "object",
      "description": "Structured entity data for ontology-typed memories. Fields are defined by the entity_type schema in the referenced ontology.",
      "required": ["name"],
      "properties": {
        "name": {
          "type": "string",
          "description": "Human-readable name for the entity"
        },
        "entity_type": {
          "type": "string",
          "pattern": "^[a-z][a-z0-9-]*$",
          "description": "Entity type from ontology (e.g., grazing-plan, soil-profile)"
        },
        "entity_id": {
          "type": "string",
          "description": "Unique identifier for this entity instance"
        }
      },
      "additionalProperties": true
    }
  }
}