You are reading the wrong documentation (yours for wgibbs-rest-client , which has not been updated since 2009): here is the correct one . But this does not say anything about the difference, although it is simple:
:open_timeout is the timeout for opening a connection. This is useful if you are calling servers with slow or shaky response times.
:timeout is the timeout for reading the response. This is useful to make sure that you donβt get stuck halfway while reading or are not stuck by reading a 5 MB file when you expect 5 KB of JSON .
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