You copied some JSON, the parser exploded, and the error says something like:

Unexpected token ' in JSON at position 2

The culprit is almost always single quotes. Here's exactly why it happens

and how to fix it safely.

Why JSON is this strict about quotes

JSON was designed to be boring on purpose. Every parser, in every language,

agrees on what a string is because the format only allows double quotes.

No exceptions.

JavaScript makes this feel confusing. Single quotes are perfectly valid

in a JS object literal — but a JS object literal is not JSON. The moment

that payload hits JSON.parse(), the JSON rules win.

The three patterns people hit most

Invalid: all single quotes

{ 'name': 'StructKit' , 'mode': 'validator' }

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Invalid: even just one

{ "name" : 'StructKit' , "mode" : "validator" }

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One single-quoted value is enough to blow up the whole payload.

Valid: double quotes throughout

{ "name" : "StructKit"…