Developer Tools

About Developer Tools

These are the small utilities that sit between the real work: formatting JSON that arrived on one line, decoding a token to see why authentication failed, checking a regular expression against real input before it reaches production, building a cron expression without re-reading the field order. Each one is designed to be readable rather than merely correct — errors point at the position that caused them, and output is formatted the way you would commit it. Everything runs locally, so pasting a production token, a query, or a payload into one of these does not send it anywhere.

That last point is the reason to use a local tool for this category specifically. A JSON payload from a real system tends to contain customer names, internal identifiers, and sometimes credentials; a token contains whatever the system put in it. Pasting either into a site that processes it on a server means handing that data to a third party, and it is the kind of thing that is discovered later rather than noticed at the time. Here the page is the program — once it has loaded, the work happens on your machine.

A note on the token tools: decoding shows you what a token claims, not whether it is valid. The signature is what makes a token trustworthy, and reading the contents tells you nothing about that. Decode to answer "what did the server think I was" and "when does this expire" — the two questions that explain most authentication failures — and check the signature where it is actually enforced.