Hermes hardcodes response_format=json_schema on its title call. No local
back-end implements constrained decoding — frank-small and frank-large both
answer 400 'response_format json_object/json_schema is not supported' — so
every session logged a title failure and fell back to a message-derived
title. The NPU endpoint that used to absorb this call was retired on
2026-09-11.
The call now goes out over the Responses transport (the only one that does
not forward response_format) with thinking off. A 64-token cap cannot hold a
thinking pass plus a title: with the default reasoning effort the model spent
all 64 tokens thinking and returned empty content, which is why disabling
reasoning is part of the fix and not decoration.
Verified against the live endpoint with the real prompt and the real
extraction path: raw {"title": "Friendly greeting"} -> title
'Friendly greeting' in 3.4s, where the previous configuration returned 400.
Frank
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