{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://git.transaction.science/Transaction-Science/open-standards/raw/branch/main/wai/wai-quantum/schemas/versions.v1.json",
  "title": "wai.quantum.versions/1",
  "description": "What a host reports of its versions: the engine's name and version, the host's own (the command line, the job service), the schema of every document it writes by its versioned name, the protocols it speaks, and where the policy and the deprecations are. wai-quantum version --json prints it; both MCP servers give it in initialize (_meta) and the job service in quantum_service_info.",
  "type": "object",
  "required": ["schema", "engine", "schemas", "policy", "deprecations"],
  "properties": {
    "schema": { "const": "wai.quantum.versions/1" },
    "engine": {
      "type": "object",
      "required": ["name", "version"],
      "properties": {
        "name": { "const": "wai-quantum" },
        "version": { "type": "string" }
      }
    },
    "host": {
      "type": "object",
      "description": "The program reporting: its crate's name and version.",
      "required": ["name", "version"],
      "properties": {
        "name": { "type": "string" },
        "version": { "type": "string" }
      }
    },
    "schemas": {
      "type": "object",
      "description": "Each document's schema, by its versioned name (wai.quantum.<document>/<major>, kept as <document>.v<major>.json).",
      "additionalProperties": { "type": "string" }
    },
    "protocols": {
      "type": "object",
      "description": "The protocols the host speaks: the Model Context Protocol versions its server answers, newest first, and the open provider protocol.",
      "properties": {
        "mcp": { "type": "array", "items": { "type": "string" } },
        "provider": { "type": "string" }
      }
    },
    "policy": { "type": "string", "description": "What is stable, for how long, and how a change is announced." },
    "deprecations": { "type": "string", "description": "Each deprecated item, the version that deprecated it, and its replacement." }
  }
}