Try beingmeta's tagger endpoint

This page documents and demonstrates the REST interface to one of beingmeta's web services. The parse service does analysis of unrestricted English text, identifying phrase and functional part of speech information.

for grammatical structure
TEXT
OUTPUT HTML (as a page) XML JSON HTML (as a fragment)
Wrap non-HTML types in HTML for browsers which don't explicitly 'accept' JSON or XML
LEXICON
URI of a custom lexicon, in LEXML format (sample)
RELOAD Reload the lexicon before using it
OPTIONS