"bon plan" meaning in French

{
  "forms": [
    {
      "form": "bons plans",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "m"
      },
      "expansion": "bon plan m (plural bons plans)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "good deal; good idea"
      ],
      "id": "en-bon_plan-fr-noun-otq7QQKi",
      "raw_glosses": [
        "(informal) good deal; good idea"
      ],
      "tags": [
        "informal",
        "masculine"
      ]
    }
  ],
  "word": "bon plan"
}

{
  "forms": [
    {
      "form": "bons plans",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "m"
      },
      "expansion": "bon plan m (plural bons plans)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "French countable nouns",
        "French entries with incorrect language header",
        "French informal terms",
        "French lemmas",
        "French masculine nouns",
        "French multiword terms",
        "French nouns"
      ],
      "glosses": [
        "good deal; good idea"
      ],
      "raw_glosses": [
        "(informal) good deal; good idea"
      ],
      "tags": [
        "informal",
        "masculine"
      ]
    }
  ],
  "word": "bon plan"
}