I\'m sure the answer to this is going to be some painfully obvious character encoding issue...
I\'m using curl on the command line to test some endpoints in a python
The answer to the question, "what am I doing wrong," is that the shell sees the ampersand (&) and thinks that's the end of the command (and puts it into the background). You need to quote it, which is why the answers that quoted the string work. You could just as easily run this:
curl -v -L "http://localhost:5000/pulse?lat=41.225&lon=-73.1"