list_sandboxes

{
  "properties": {
    "kind": {
      "description": "What this result is — 'cell.read', 'notebooks.list' and so on. Lets a client tell one answer from another without matching prose.",
      "title": "Kind",
      "type": "string"
    },
    "result": {
      "default": null,
      "description": "The answer itself: a message, the rows of a listing, or the outputs of an execution in order.",
      "title": "Result"
    }
  },
  "required": [
    "kind"
  ],
  "type": "object",
  "additionalProperties": true,
  "description": "What every tool of this server answers with.\n\nDeclared so the shape is *advertised* rather than merely produced. A tool\nthat returns structure without saying what it will return leaves a client\nnothing to validate against and the generated reference nothing to show —\nthe call works and the contract is invisible, which is the worst of both.\n\nExtra fields are allowed on purpose. A tool that already answers with a\nmapping keeps its own keys (see :func:`_default_shape`), and those are the\ninteresting part of its answer; forbidding them would mean either\nflattening every tool into one shape or declaring nothing at all.",
  "title": "ToolAnswer"
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "list_sandboxes",
    "arguments": {}
  }
}

result = await session.call_tool("list_sandboxes", arguments={})