PyJWT

PyJWT provides a straightforward API for encoding and decoding JWTs that's easy to pick up. The core `jwt.encode()` and `jwt.decode()` functions are intuitive, and the library handles the most common use cases well. Type hints are present but could be more comprehensive - you'll find yourself checking docs for payload structure expectations. The algorithm parameter is required and explicit, which is good for security but can trip up newcomers.

The biggest pain point is error handling. The library raises generic exceptions like `DecodeError` and `InvalidSignatureError`, but the messages aren't always helpful for debugging. When tokens fail validation, you often need to decode without verification first to inspect what's wrong. The `options` parameter for skipping certain validations is powerful but poorly documented - you'll discover most flags through trial and error or Stack Overflow.

Documentation covers basics adequately with working examples, but advanced scenarios like key rotation, custom claims validation, and JWK handling require digging through source code. The API has remained stable across versions, making upgrades painless.

PyJWT provides a clean, minimal API for JWT operations that feels natural once you understand the basics. The encode/decode functions are intuitive, and the library correctly handles the security aspects by default (like requiring algorithm specification during decode). Type hints are present but could be more specific - many return types are just 'str' or 'dict' without detailed typing.

The biggest pain point is error handling. When tokens fail validation, you get generic exceptions that don't clearly explain what went wrong. Expired tokens throw 'ExpiredSignatureError' which is good, but invalid signatures, malformed tokens, and missing claims all require careful exception catching and debugging. The documentation covers the happy path well with solid examples, but troubleshooting guidance is minimal.

Day-to-day usage is smooth for standard JWT workflows. The algorithms parameter requirement prevents security issues but trips up newcomers. IDE autocomplete works adequately, though the library's type stubs could provide richer hints for payload structures and registered claims.

PyJWT is straightforward and does exactly what it says on the tin. The core encode/decode API is clean and the library handles the cryptographic heavy lifting reliably. Performance is solid for typical web application loads - token operations are fast enough that they've never shown up in our profiling. Memory footprint is minimal since tokens are stateless strings.

The library has improved significantly around algorithm security. The 2.x versions require explicit algorithm specification during decode, which prevents the notorious 'none' algorithm vulnerability - but this was a breaking change that caught many teams off guard during upgrades. Error handling is Python-exception based (ExpiredSignatureError, InvalidTokenError, etc.) which integrates well with standard try/except patterns. The decode() method doesn't do any I/O, so there's no connection pooling concerns, but you'll need to build your own key rotation and JWK fetching layer.

Configuration is dictionary-based with sensible defaults, though there's no built-in logging or observability hooks - you'll wrap this yourself. Watch out for the `verify=True` parameter becoming `options={'verify_signature': True}` between versions. Time-based claim validation (exp, nbf) respects leeway parameters which is crucial for distributed systems with clock skew.