"all serene" meaning in English

{
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              1,
              11
            ]
          ],
          "ref": "1887, Talbot Baines Reed, The Willoughby Captains, page 201:",
          "text": "“All serene,” cried the jubilant voice outside, “open the door, you fellows!”",
          "type": "quote"
        },
        {
          "ref": "1893, American Illustrated Magazine (volume 36, page 482)",
          "text": "\"All serene, old un — but 'ave yer got the brads (money) to pay for it?\" said Bill, sneeringly, with another scornful glance at his fare's humble exterior."
        }
      ],
      "glosses": [
        "All is well; a cry of acquiescence or approval."
      ],
      "id": "en-all_serene-en-intj-FdCzfpQS",
      "links": [
        [
          "well",
          "well"
        ],
        [
          "acquiescence",
          "acquiescence#English"
        ],
        [
          "approval",
          "approval#English"
        ]
      ],
      "raw_glosses": [
        "(obsolete, slang) All is well; a cry of acquiescence or approval."
      ],
      "tags": [
        "obsolete",
        "slang"
      ]
    }
  ],
  "word": "all serene"
}

{
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English interjections",
        "English lemmas",
        "English multiword terms",
        "English slang",
        "English terms with obsolete senses",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries",
        "Quotation templates to be cleaned"
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              1,
              11
            ]
          ],
          "ref": "1887, Talbot Baines Reed, The Willoughby Captains, page 201:",
          "text": "“All serene,” cried the jubilant voice outside, “open the door, you fellows!”",
          "type": "quote"
        },
        {
          "ref": "1893, American Illustrated Magazine (volume 36, page 482)",
          "text": "\"All serene, old un — but 'ave yer got the brads (money) to pay for it?\" said Bill, sneeringly, with another scornful glance at his fare's humble exterior."
        }
      ],
      "glosses": [
        "All is well; a cry of acquiescence or approval."
      ],
      "links": [
        [
          "well",
          "well"
        ],
        [
          "acquiescence",
          "acquiescence#English"
        ],
        [
          "approval",
          "approval#English"
        ]
      ],
      "raw_glosses": [
        "(obsolete, slang) All is well; a cry of acquiescence or approval."
      ],
      "tags": [
        "obsolete",
        "slang"
      ]
    }
  ],
  "word": "all serene"
}