You're debugging an auth issue. There's a JWT in a log line, or in an Authorization header you copied out of the network tab. You need to know two things: what's in it, and has it expired?
So you do what everyone does — paste it into jwt.io.
Stop for a second. That token is often a live credential. You just pasted it into a third-party web page: it's in your browser history, maybe in someone's logs, maybe cached. For a token that's still valid, that's a real problem.
The other option is the pipeline nobody can remember:
echo "$TOKEN" | cut -d. -f2 | base64 -d 2>/dev/null | python -m json.tool
