{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://alxprotocol.com/protocol/1/schemas/extension-manifest.schema.json",
  "title": "ALX Extension Manifest",
  "description": "Machine-readable lifecycle metadata for an ALX Protocol extension.",
  "$comment": "This schema validates manifest shape only; compatibility semantics remain defined by the protocol spec and conformance policy.",
  "type": "object",
  "properties": {
    "id": {
      "type": "string",
      "pattern": "^[a-z][a-z0-9-]{2,63}$",
      "description": "Extension identifier. Lowercase alphanumeric with hyphens, 3–64 characters."
    },
    "extensionVersion": {
      "$ref": "./defs.schema.json#/$defs/semver",
      "description": "Extension version following semantic versioning."
    },
    "lifecycle": {
      "enum": ["draft", "provisional", "stable", "deprecated", "withdrawn"],
      "description": "Current lifecycle stage of the extension."
    },
    "requiredForCore": {
      "type": "boolean",
      "description": "True if this extension is required for core protocol conformance. False for optional extensions."
    },
    "compatibleProtocolVersions": {
      "type": "array",
      "items": {
        "type": "string",
        "pattern": "^[1-9][0-9]*$"
      },
      "minItems": 1,
      "uniqueItems": true,
      "description": "ALX Protocol major versions this extension is compatible with."
    },
    "deprecated": {
      "type": "boolean",
      "description": "True if this extension is deprecated. Use the lifecycle field for the canonical deprecation state."
    },
    "supersedes": {
      "type": ["string", "null"],
      "description": "Identifier of the extension this extension replaces, or null if it does not supersede another."
    },
    "vectors": {
      "type": "array",
      "description": "Test vector files associated with this extension.",
      "items": {
        "type": "object",
        "properties": {
          "id": {
            "type": "string",
            "minLength": 3,
            "maxLength": 128,
            "pattern": "^[a-z][a-z0-9.-]*[a-z0-9]$"
          },
          "path": { "$ref": "#/$defs/relativeSafePath" }
        },
        "required": ["id", "path"],
        "additionalProperties": false
      }
    },
    "runner": {
      "description": "Test execution strategy for this extension's vectors.",
      "oneOf": [
        {
          "type": "object",
          "properties": {
            "type": { "const": "schema-only" }
          },
          "required": ["type"],
          "additionalProperties": false
        },
        {
          "type": "object",
          "properties": {
            "type": { "const": "cli" },
            "command": {
              "type": "string",
              "pattern": "^[a-zA-Z0-9._-]+$"
            },
            "args": {
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 128,
                "pattern": "^[a-zA-Z0-9._-]+$"
              },
              "maxItems": 16
            }
          },
          "required": ["type", "command", "args"],
          "additionalProperties": false
        }
      ]
    },
    "schemas": {
      "type": "array",
      "description": "JSON Schema files provided by this extension.",
      "items": {
        "type": "object",
        "properties": {
          "id": { "type": "string", "pattern": "^[a-z][a-z0-9-]{2,63}$" },
          "path": { "$ref": "#/$defs/relativeSafePath" }
        },
        "required": ["id", "path"],
        "additionalProperties": false
      }
    },
    "errorCodes": {
      "$ref": "#/$defs/relativeSafePath",
      "description": "Error registry provided by this extension."
    }
  },
  "required": [
    "id",
    "extensionVersion",
    "lifecycle",
    "requiredForCore",
    "compatibleProtocolVersions",
    "deprecated",
    "supersedes",
    "vectors",
    "runner"
  ],
  "additionalProperties": false,
  "$defs": {
    "relativeSafePath": {
      "type": "string",
      "minLength": 1,
      "maxLength": 512,
      "pattern": "^(?!/)(?![A-Za-z]:)(?!.*\\.\\.)([a-zA-Z0-9._/-]+)$"
    }
  }
}