The frontend hardcoded think=true on every chat send (ChatPanel full +
widget variants, KnowledgeView minichat), which defeated the _should_think
gate on the backend and made qwen3:14b spend 5-20s on chain-of-thought
reasoning for every turn — even "hi". This was the root cause of the
warm-path TTFT variance tracked in followup_ttft_variance.md: the logged
ttft_ms was really prefill + full thinking phase, bouncing with the depth
of the model's reasoning, not with cache or eviction.
All three frontend callers now pass think=false and let _should_think be
authoritative. The classifier is now a real content-based gate: explicit
think_requested=True still forces on as an override (briefing discuss
actions, future UI toggles, MCP callers), otherwise messages <80 chars
without reasoning keywords skip thinking, messages >=400 chars or
containing keywords like why/explain/analyze/debug/review/etc. get it.
Generation timing now separately records think_requested, the final
think decision, first_token_ms (first any chunk), and thinking_ms
(duration of the thinking phase). ttft_ms keeps its existing semantic
(first content token) so existing log analysis still works. The timing
log line surfaces all four fields so the old "just a big ttft number"
ambiguity is gone.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
bvandeusen
87fcaa6a0d