When yt-dlp is installed but stale (or otherwise unable to fetch transcripts
for any returned videos), runs previously reported YouTube as fully
successful in two user-facing surfaces:
1. Footer (render.py): showed "N videos | M views" with no indication
that zero transcripts were captured. The "with transcripts" segment
was conditionally suppressed when the count was zero - converting
the canonical stale-binary failure mode into a silent absence at
the very surface users read for "did this work?".
2. Quality nudge (quality_nudge.py): classified YouTube as "active"
based purely on yt-dlp installation + absence of a top-level error.
Per-video transcript-fetch ratio was never inspected. A run that
returned N videos with 0 transcripts (canonical stale-binary
failure) was reported as fully active.
The engine itself logs the failure correctly at default stderr level
(`[YouTube] Got transcripts for 0/N videos (N failed)`), but that line
gets buried in 100+ lines of parallel-source progress output and is
contradicted by the success-shaped footer and nudge that follow.
This change makes both conclusion surfaces honest:
* render.py footer always renders "M/N with transcripts" so the ratio
is visible regardless of value. Zero is no longer hidden. Format is
M/N (not bare M) so the denominator is in the message and the user
does not have to cross-reference the "videos" count.
* quality_nudge.py adds a third tier between "active" and "missing":
"degraded". Triggered when yt-dlp is installed AND videos were
returned AND transcript-fetch ratio is below threshold (default 50%,
tunable via DEGRADED_TRANSCRIPT_THRESHOLD env var). Emits an
actionable nudge: "YouTube returned N videos but only M transcripts
captured. The most common cause is a stale yt-dlp binary - YouTube's
caption format changes frequently and old binaries silently fail
every transcript. Update via your package manager: scoop update
yt-dlp (Windows), brew upgrade yt-dlp (macOS), or pip install -U
yt-dlp."
* last30days.py populates youtube_videos_count and
youtube_transcripts_count in the research_results dict it passes to
compute_quality_score, enabling the new degraded check at the call
site.
Threshold rationale: 50% accommodates a few legitimate
caption-disabled videos in a multi-video result, but a stale-binary
run that fails every transcript trips the nudge cleanly.
Score impact: degradation is informational, not score-affecting.
YouTube still counts as "active" in score_pct so users do not see
their score drop for a fixable client-side issue. The nudge directs
them to their own package manager.
Tests:
* tests/test_quality_nudge.py: 6 new TestYouTubeDegraded cases cover
zero-transcripts-flags-degraded, partial-above-threshold-does-not-flag,
zero-videos-does-not-flag (no false positives on absence),
one-of-three-flags-degraded, threshold-tunable-via-config, and
degraded-does-not-affect-score.
* tests/test_render_v3.py: 4 new YoutubeFooterTranscriptRatioTests
cases cover zero-transcripts-with-videos-renders-zero-over-total
(the regression repro), partial-renders-ratio, full-renders-ratio,
and no-videos-suppresses-entire-segment.
All 29 new test cases verified GREEN with the fix and RED without it
(temp-reverted both files separately to confirm each test catches the
specific regression it asserts).
Integration validation: ran the engine against an intentionally stale
yt-dlp 2025.03.31 binary placed first on PATH. Pre-fix the footer
showed `YouTube: 3 videos | 386,815 views` (no transcript signal).
Post-fix the footer shows `YouTube: 3 videos | 386,815 views | 0/3
with transcripts` and stderr emits "Degraded: YouTube" plus the
actionable update-yt-dlp nudge.
Out of scope (deserves its own PR): exposing transcripts_captured in
the EVIDENCE FOR SYNTHESIS block so the synthesizing model can flag
degradation in prose. Larger schema-touching change.
Daniel Zivkovic
0a5102e193