@olivierlambert yes I think so.

Here is the result of /rest/v0/pools/_/actions/create_vm (there is no cpu parameter)
{
  "params": {
    "affinity": {
      "type": "string",
      "optional": true
    },
    "auto_poweron": {
      "type": "boolean",
      "optional": true
    },
    "boot": {
      "type": "boolean",
      "default": false
    },
    "clone": {
      "type": "boolean",
      "default": true
    },
    "cloud_config": {
      "type": "string",
      "optional": true
    },
    "destroy_cloud_config_vdi": {
      "type": "boolean",
      "default": false
    },
    "install": {
      "type": "object",
      "optional": true,
      "properties": {
        "method": {
          "enum": [
            "cdrom",
            "network"
          ]
        },
        "repository": {
          "type": "string"
        }
      }
    },
    "memory": {
      "type": "integer",
      "optional": true
    },
    "name_description": {
      "type": "string",
      "minLength": 0,
      "optional": true
    },
    "name_label": {
      "type": "string"
    },
    "network_config": {
      "type": "string",
      "optional": true
    },
    "template": {
      "type": "string"
    },
    "vdis": {
      "type": "array",
      "default": [],
      "items": {
        "type": "object",
        "properties": {
          "destroy": {
            "type": "boolean",
            "optional": true
          },
          "userdevice": {
            "type": "string",
            "optional": true
          },
          "size": {
            "type": "number",
            "optional": true
          },
          "sr": {
            "type": "string",
            "optional": true
          },
          "name_description": {
            "type": "string",
            "optional": true
          },
          "name_label": {
            "type": "string",
            "optional": true
          }
        },
        "if": {
          "not": {
            "required": [
              "userdevice"
            ]
          }
        },
        "then": {
          "required": [
            "size",
            "name_label"
          ],
          "not": {
            "required": [
              "destroy"
            ]
          }
        }
      }
    },
    "vifs": {
      "default": [],
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "destroy": {
            "type": "boolean",
            "optional": true
          },
          "device": {
            "type": "string",
            "optional": true
          },
          "ipv4_allowed": {
            "type": "array",
            "items": {
              "type": "string"
            },
            "optional": true
          },
          "ipv6_allowed": {
            "type": "array",
            "items": {
              "type": "string"
            },
            "optional": true
          },
          "mac": {
            "type": "string",
            "optional": true
          },
          "network": {
            "type": "string",
            "optional": true
          }
        }
      }
    }
  }
}