{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://go-sip.local/contracts/proposals/task-discovery-v0.1-proposal.schema.json",
  "title": "Project-local contract: Dispatcher task discovery responses; external compatibility unverified",
  "oneOf": [
    {"$ref": "#/$defs/snapshot_response"},
    {"$ref": "#/$defs/changes_response"},
    {"$ref": "#/$defs/error_response"}
  ],
  "$defs": {
    "dispatcher_id": {
      "type": "string",
      "format": "uuid",
      "pattern": "^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$"
    },
    "cursor": {
      "type": "string",
      "minLength": 1,
      "maxLength": 512,
      "$comment": "Opaque SaaS change watermark; never compare to task_id or infer numeric order."
    },
    "task_fields": {
      "type": "object",
      "required": ["task_id", "tenant_id", "tenant_key", "status", "task_revision"],
      "properties": {
        "task_id": {"type": "string", "pattern": "^[A-Za-z0-9_-]{1,128}$"},
        "tenant_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "tenant_key": {
          "type": "string",
          "minLength": 1,
          "maxLength": 196,
          "$comment": "Also validate the existing UTF-8 byte limit and tenant_id mapping in business logic; tenant_key is not part of any queue or routing key."
        },
        "status": {"enum": ["running", "paused", "stopped", "finished"]},
        "task_revision": {"type": "integer", "minimum": 1}
      }
    },
    "queue": {
      "type": "object",
      "additionalProperties": false,
      "required": ["exchange", "routing_key", "binding_key", "queue_name"],
      "properties": {
        "exchange": {"const": "agent-call.dispatchers.v3"},
        "routing_key": {"type": "string", "maxLength": 175, "pattern": "^d\\.[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}\\.task\\.[A-Za-z0-9_-]{1,128}\\.in$"},
        "binding_key": {"type": "string", "maxLength": 175, "pattern": "^d\\.[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}\\.task\\.[A-Za-z0-9_-]{1,128}\\.in$"},
        "queue_name": {"type": "string", "maxLength": 186, "pattern": "^agent-call\\.d\\.[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}\\.task\\.[A-Za-z0-9_-]{1,128}\\.v3$"}
      },
      "$comment": "SaaS-created and managed queue address; D only consumes. Runtime derives names from dispatcher_id/task_id, requires binding_key = routing_key, and rejects mismatches. Max 256 assigned or draining task queues per D."
    },
    "snapshot_task": {
      "allOf": [
        {"$ref": "#/$defs/task_fields"},
        {
          "type": "object",
          "required": ["queue"],
          "properties": {"queue": {"$ref": "#/$defs/queue"}}
        }
      ],
      "unevaluatedProperties": false
    },
    "changed_task": {
      "allOf": [
        {"$ref": "#/$defs/task_fields"},
        {
          "type": "object",
          "required": ["cursor", "operation", "queue"],
          "properties": {
            "cursor": {"$ref": "#/$defs/cursor"},
            "operation": {"enum": ["assigned", "updated"]},
            "queue": {"$ref": "#/$defs/queue"}
          }
        }
      ],
      "unevaluatedProperties": false
    },
    "removed_task": {
      "type": "object",
      "additionalProperties": false,
      "required": ["cursor", "operation", "task_id", "tenant_id", "tenant_key"],
      "properties": {
        "cursor": {"$ref": "#/$defs/cursor"},
        "operation": {"const": "removed"},
        "task_id": {"type": "string", "pattern": "^[A-Za-z0-9_-]{1,128}$"},
        "tenant_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "tenant_key": {
          "type": "string",
          "minLength": 1,
          "maxLength": 196,
          "$comment": "Also validate the existing UTF-8 byte limit and tenant_id mapping in business logic."
        }
      }
    },
    "snapshot_response": {
      "type": "object",
      "additionalProperties": false,
      "required": ["schema_version", "dispatcher_id", "mode", "snapshot_id", "cursor", "tasks", "next_page_token"],
      "properties": {
        "schema_version": {"const": "task-discovery.v0.1-proposal"},
        "dispatcher_id": {"$ref": "#/$defs/dispatcher_id"},
        "mode": {"const": "snapshot"},
        "snapshot_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "cursor": {"$ref": "#/$defs/cursor"},
        "tasks": {"type": "array", "maxItems": 100, "items": {"$ref": "#/$defs/snapshot_task"}},
        "next_page_token": {"type": ["string", "null"], "minLength": 1, "maxLength": 512}
      },
      "$comment": "Each page has at most 100 tasks. All pages retain the first page's snapshot_id/cursor; stage and persist all pages before atomically replacing the active snapshot and advancing the cursor."
    },
    "changes_response": {
      "type": "object",
      "additionalProperties": false,
      "required": ["schema_version", "dispatcher_id", "mode", "from_cursor", "next_cursor", "changes", "next_page_token"],
      "properties": {
        "schema_version": {"const": "task-discovery.v0.1-proposal"},
        "dispatcher_id": {"$ref": "#/$defs/dispatcher_id"},
        "mode": {"const": "changes"},
        "from_cursor": {"$ref": "#/$defs/cursor"},
        "next_cursor": {"$ref": "#/$defs/cursor"},
        "changes": {
          "type": "array",
          "maxItems": 100,
          "items": {
            "oneOf": [
              {"$ref": "#/$defs/changed_task"},
              {"$ref": "#/$defs/removed_task"}
            ]
          }
        },
        "next_page_token": {"type": ["string", "null"], "minLength": 1, "maxLength": 512}
      },
      "$comment": "Each page has at most 100 changes. All pages retain from_cursor/next_cursor for the same window; apply changes in response order and persist all pages before atomically advancing next_cursor. Cursor and page-token continuity are cross-response semantics."
    },
    "error_response": {
      "type": "object",
      "additionalProperties": false,
      "required": ["schema_version", "resource", "error"],
      "properties": {
        "schema_version": {"const": "task-discovery.v0.1-proposal"},
        "resource": {"const": "error"},
        "error": {
          "type": "object",
          "$comment": "Local HTTP mapping: invalid_cursor/invalid_page_token=400, unauthorized=401, dispatcher_not_authorized=403, cursor_expired/snapshot_expired=410, service_unavailable=503. Status is transport metadata and is not part of the JSON body; external SaaS compatibility is unverified.",
          "additionalProperties": false,
          "required": ["code", "message"],
          "properties": {
            "code": {"enum": ["invalid_cursor", "cursor_expired", "snapshot_expired", "invalid_page_token", "unauthorized", "dispatcher_not_authorized", "service_unavailable"]},
            "message": {"type": "string", "minLength": 1, "maxLength": 256}
          }
        }
      }
    }
  }
}