How to make comment in JSON file

comments-trick.json

{
    "//field": "These 'double quote' 'double quote' are used as comments, because JSON doesnt' allow comment",
    "field": {},
    "#another-field": "Another comment",
    "another-field": {},
    "/*stuff": "Be careful to use them when you have full control of the content :)",
    "stuff": [],
    "bla": "bla"
}

Because JSON is a subset of YAML, # should be used as comment character. IMHO :-) but as with everything one could argue about it
The YAML port: 8090 #can't use native port
could be converted to
a) "port": 8090, "#can't use native port":""
b) "port": 8090, "#":"can't use native port"

Change the file extension to .json5 and you can haz comments 🙂

try JSON5 or JSONC

https://json5.org/

https://code.visualstudio.com/docs/languages/json#_json-with-comments

I found it

Hjson, at https://hjson.github.io/, works better for me than JSON5. YMMV.

Its Python module has been maintained more recently and its documentation shows the syntax of multiline comments as well as #-based comments.

You can create a special key in your JSON Mapquest Directions object to store comments. This key would be ignored by any JSON parsers that don't use it, but it allows you to include notes.