JWT errors often look specific, but the message is only the starting point. The fastest way to debug...
JWT errors often look specific, but the message is only the starting point. The fastest way to debug them is to separate token shape, signature verification, and claim validation instead of changing keys or expiration settings at random.
Here is the checklist I use.
1. Start with the token shape
A compact JWT normally contains three Base64URL-encoded segments:
header.payload.signature
If you've ever worked with auth, you've seen a JWT — a long string like eyJhbGci... split into three...
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