This afternoon (UTC), the API got overloaded for a while; you may have
noticed slow responses or HTTP 504s. Tim tried to solve this by
disabling action=parse, which worked surprisingly well. This means
action=parse is disabled for now and will remain disabled until I
figure out what was going on at the time of the outage.
In the meantime, the API will act as though the action=parse module
doesn't exist, so you'll get errors along the lines of "unknown value
for parameter action: 'parse'".
I'll re-enable action=parse once I'm relatively confident it won't
cause the entire API to melt down again.
Roan Kattouw (Catrope)