Repeated HSFETCH queries fail with QUERY_NO_HSDIR

Hi lovely network team. Iain is working on a script to inform him of hidden service descriptor age. He's using stem to fetch them but unfortunately after a few HSFETCH calls it begins to fail with QUERY_NO_HSDIR. Maybe some attempt at rate limiting? Once the tor process gets into a borked state it doesn't seem to recover until I bounce the tor process.

Here's an example of my first query (which succeeds)...

>>> SETEVENTS HS_DESC HS_DESC_CONTENT
250 OK

>>> HSFETCH facebookcorewwwi
250 OK

>>> /events
HS_DESC_CONTENT facebookcorewwwi 3jjxhgi72xguhnihk4nwzrcpyvwf3ml5 $DA722ECCB9C0DE462C4FA585B93C99CCCA1C7547~SIRDRAKE2018
rendezvous-service-descriptor 3jjxhgi72xguhnihk4nwzrcpyvwf3ml5
version 2
permanent-key
-----BEGIN RSA PUBLIC KEY-----
MIGJAoGBALfng/krEfrBcvblDiM3PAkowkiAKxLoTsXt3nPEzyTP6Cw+Gdr0ODje
hmxTngN1pKiH7szk4Q1p2RabOrUHWwXmGXeDDNs00fcyU6HupgqsCoKOqCsmPac6
/58apC64A7xHeS02wtfWJp6qiZ8i6GGu6xWXRWux+ShPgcHvkajRAgMahU8=
-----END RSA PUBLIC KEY-----
secret-id-part wuyfue4erz2hlh4d5o4kduweosco6rw4
publication-time 2018-10-31 18:00:00
protocol-versions 2,3
introduction-points
-----BEGIN MESSAGE-----
aW50cm9kdWN0aW9uLXBvaW50IHR6c3U3ZXh5amVlZWU2cm92cDd1Z25lM3pxemlo
ZHk1CmlwLWFkZHJlc3MgMTQ0Ljc2Ljk2LjYKb25pb24tcG9ydCA5MDAxCm9uaW9u
... lot more base64...
L1UycythTGNtYmhITGJPWlhZRjRMcERTV1R3THkwb0ZzTEFnTUJBQUU9Ci0tLS0t
RU5EIFJTQSBQVUJMSUMgS0VZLS0tLS0KCg==
-----END MESSAGE-----
signature
-----BEGIN SIGNATURE-----
cMLWu42NG+I5hH9QAHZUQ8eDGCUzcny/uN/FwAYiLsUSc3QLg7MKbRTZ3v2ARonB
wcUgEAGpO4wDjuEj2ivNmpt6U0smJ7nM5KTWy4l0732QnTeSEX+P53qIJ7KwxDro
+JyBARfK4orCMieHuxYtJop6YgVRQ8XN6NtP6NiDrWY=
-----END SIGNATURE-----
OK
HS_DESC RECEIVED facebookcorewwwi NO_AUTH $DA722ECCB9C0DE462C4FA585B93C99CCCA1C7547~SIRDRAKE2018 3jjxhgi72xguhnihk4nwzrcpyvwf3ml5
HS_DESC REQUESTED facebookcorewwwi NO_AUTH $DA722ECCB9C0DE462C4FA585B93C99CCCA1C7547~SIRDRAKE2018 3jjxhgi72xguhnihk4nwzrcpyvwf3ml5

... and here's an example of my fourth onward, which always fail.

>>> /events clear
cleared event backlog

>>> HSFETCH facebookcorewwwi
250 OK

>>> /events
HS_DESC_CONTENT facebookcorewwwi 3jjxhgi72xguhnihk4nwzrcpyvwf3ml5 UNKNOWN

OK
HS_DESC FAILED facebookcorewwwi NO_AUTH UNKNOWN REASON=QUERY_NO_HSDIR
HS_DESC_CONTENT facebookcorewwwi csq76xfzmtyepzmkhzz2lb7ja3vmylwu UNKNOWN

OK
HS_DESC FAILED facebookcorewwwi NO_AUTH UNKNOWN REASON=QUERY_NO_HSDIR

I'm filing this on irl's behalf. If anything's needed from me on the stem front just let me know.