feat(discovery): drop Shorts and livestreams before the caption fetch (ADR-023)

The scarce resource is the per-IP timedtext caption fetch (ADR-014); the pilot's
candidate set was mostly Shorts/clips/livestreams, each burning a fetch (a "none"
result is a completed fetch — it costs budget even when it yields nothing).

NewVideos now enriches candidates with one cheap Data API videos.list call
(contentDetails.duration + snippet.liveBroadcastContent — the quota API, a
DIFFERENT limit from the timedtext 429) and drops, before returning: videos
shorter than TAPIR_MIN_VIDEO_SECONDS (default 60) and any live/upcoming
broadcast. Dropped videos are never persisted, so the list declutters too.

Degrade-open: MinVideoSeconds=0 disables it (no quota call); a videos.list error
returns candidates unfiltered so discovery never breaks on a metadata hiccup. The
paste-a-URL path (VideoByID) is not filtered — an explicit request is honoured.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/adapters/youtube/youtube.go

@@ -66,6 +66,13 @@ type Config struct {
 	// poll. Zero means defaultMaxVideos.
 	MaxVideosPerSubscription int
 
+	// MinVideoSeconds drops videos shorter than this from discovery (Shorts/clips,
+	// ADR-023). NewVideos enriches candidates with a single cheap videos.list call
+	// (contentDetails.duration + snippet.liveBroadcastContent) and filters before
+	// returning, so the scarce caption-fetch budget is never spent on them. Live
+	// and upcoming broadcasts are dropped too. Zero disables the filter.
+	MinVideoSeconds int
+
 	// BaseURL overrides the Data API root. Empty means defaultBaseURL.
 	BaseURL string
 
@@ -242,7 +249,97 @@ func (a *Adapter) NewVideos(ctx context.Context, sub domain.Subscription) ([]dom
 			break
 		}
 	}
-	return videos, nil
+
+	// Drop Shorts/sub-minute clips and live/upcoming broadcasts before they ever
+	// reach the rate-limited caption path (ADR-023). One cheap videos.list call
+	// (quota API, not the timedtext throttle) supplies duration + live status.
+	return a.filterLowValue(ctx, client, videos), nil
+}
+
+// filterLowValue removes videos shorter than cfg.MinVideoSeconds and any live or
+// upcoming broadcast, using a single videos.list lookup for duration +
+// liveBroadcastContent. The filter is best-effort: if MinVideoSeconds is 0 (off)
+// or the lookup fails, the input is returned unfiltered — discovery must not break
+// because a metadata call hiccuped; the worst case is the pre-ADR-023 behaviour.
+func (a *Adapter) filterLowValue(ctx context.Context, client *http.Client, videos []domain.Video) []domain.Video {
+	if a.cfg.MinVideoSeconds <= 0 || len(videos) == 0 {
+		return videos
+	}
+
+	ids := make([]string, 0, len(videos))
+	for _, v := range videos {
+		ids = append(ids, v.ProviderVideoID)
+	}
+	q := url.Values{
+		"part": {"contentDetails,snippet"},
+		"id":   {strings.Join(ids, ",")},
+	}
+	var resp videoListResponse
+	if err := a.getJSON(ctx, client, "/videos", q, &resp); err != nil {
+		// Degrade open: keep the candidates rather than lose discovery.
+		return videos
+	}
+
+	type meta struct {
+		seconds int
+		live    string
+	}
+	byID := make(map[string]meta, len(resp.Items))
+	for _, it := range resp.Items {
+		byID[it.ID] = meta{seconds: parseISO8601Seconds(it.ContentDetails.Duration), live: it.Snippet.LiveBroadcastContent}
+	}
+
+	kept := videos[:0]
+	for _, v := range videos {
+		m, ok := byID[v.ProviderVideoID]
+		if !ok {
+			kept = append(kept, v) // unknown metadata: keep, let the fetch decide
+			continue
+		}
+		if m.live != "" && m.live != "none" {
+			continue // live or upcoming broadcast
+		}
+		if m.seconds > 0 && m.seconds < a.cfg.MinVideoSeconds {
+			continue // Short / sub-threshold clip
+		}
+		kept = append(kept, v)
+	}
+	return kept
+}
+
+// parseISO8601Seconds parses an ISO 8601 duration as returned by the YouTube Data
+// API (e.g. "PT1H2M3S", "PT45S", "PT3M") into seconds. Only the hour/minute/second
+// components YouTube emits are handled; an unparseable or zero value returns 0,
+// which the caller treats as "unknown" (not filtered on duration).
+func parseISO8601Seconds(d string) int {
+	if !strings.HasPrefix(d, "PT") {
+		return 0
+	}
+	d = d[2:]
+	total, num := 0, 0
+	seen := false
+	for _, r := range d {
+		switch {
+		case r >= '0' && r <= '9':
+			num = num*10 + int(r-'0')
+			seen = true
+		case r == 'H':
+			total += num * 3600
+			num, seen = 0, false
+		case r == 'M':
+			total += num * 60
+			num, seen = 0, false
+		case r == 'S':
+			total += num
+			num, seen = 0, false
+		default:
+			return 0 // unexpected component (days/weeks) — treat as unknown
+		}
+	}
+	if seen {
+		return 0 // trailing digits without a unit: malformed
+	}
+	return total
 }
 
 // VideoByID fetches a single video's metadata (videos.list, snippet) for an
@@ -377,11 +474,16 @@ type playlistItemListResponse struct {
 
 type videoListResponse struct {
 	Items []struct {
+		ID      string `json:"id"`
 		Snippet struct {
-			Title        string    `json:"title"`
-			ChannelTitle string    `json:"channelTitle"`
-			PublishedAt  time.Time `json:"publishedAt"`
+			Title                string    `json:"title"`
+			ChannelTitle         string    `json:"channelTitle"`
+			PublishedAt          time.Time `json:"publishedAt"`
+			LiveBroadcastContent string    `json:"liveBroadcastContent"`
 		} `json:"snippet"`
+		ContentDetails struct {
+			Duration string `json:"duration"` // ISO 8601, e.g. "PT1M30S"
+		} `json:"contentDetails"`
 	} `json:"items"`
 }
 

internal/adapters/youtube/youtube_test.go

@@ -186,6 +186,91 @@ func TestNewVideosCapsAtMax(t *testing.T) {
 	}
 }
 
+// TestNewVideosFiltersShortsAndLive: with MinVideoSeconds set, discovery enriches
+// candidates via videos.list and drops sub-threshold clips (Shorts) and
+// live/upcoming broadcasts before they reach the rate-limited caption path.
+func TestNewVideosFiltersShortsAndLive(t *testing.T) {
+	a, _ := newTestAdapter(t, func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/playlistItems":
+			_, _ = w.Write([]byte(`{
+				"items": [
+					{"snippet": {"title": "Real Talk", "publishedAt": "2026-06-03T10:00:00Z", "resourceId": {"videoId": "long1"}}},
+					{"snippet": {"title": "A Short", "publishedAt": "2026-06-03T09:00:00Z", "resourceId": {"videoId": "short1"}}},
+					{"snippet": {"title": "Live Now", "publishedAt": "2026-06-03T08:00:00Z", "resourceId": {"videoId": "live1"}}}
+				]
+			}`))
+		case "/videos":
+			if got := r.URL.Query().Get("part"); got != "contentDetails,snippet" {
+				t.Errorf("videos.list part=%q, want contentDetails,snippet", got)
+			}
+			_, _ = w.Write([]byte(`{
+				"items": [
+					{"id": "long1", "contentDetails": {"duration": "PT12M30S"}, "snippet": {"liveBroadcastContent": "none"}},
+					{"id": "short1", "contentDetails": {"duration": "PT45S"}, "snippet": {"liveBroadcastContent": "none"}},
+					{"id": "live1", "contentDetails": {"duration": "PT0S"}, "snippet": {"liveBroadcastContent": "live"}}
+				]
+			}`))
+		default:
+			t.Errorf("unexpected path %q", r.URL.Path)
+		}
+	})
+	a.cfg.MinVideoSeconds = 60
+
+	vids, err := a.NewVideos(context.Background(), domain.Subscription{ID: "s1", UserID: "u1", ChannelID: "UC_acme"})
+	if err != nil {
+		t.Fatalf("NewVideos: %v", err)
+	}
+	if len(vids) != 1 || vids[0].ProviderVideoID != "long1" {
+		t.Fatalf("expected only long1 to survive the filter, got %+v", vids)
+	}
+}
+
+// TestNewVideosNoFilterWhenDisabled: MinVideoSeconds=0 keeps the pre-ADR-023
+// behaviour — no videos.list call, no filtering.
+func TestNewVideosNoFilterWhenDisabled(t *testing.T) {
+	a, _ := newTestAdapter(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/videos" {
+			t.Errorf("videos.list must not be called when MinVideoSeconds is 0")
+		}
+		_, _ = w.Write([]byte(`{"items": [
+			{"snippet": {"title": "A Short", "publishedAt": "2026-06-03T09:00:00Z", "resourceId": {"videoId": "short1"}}}
+		]}`))
+	})
+	a.cfg.MinVideoSeconds = 0
+
+	vids, err := a.NewVideos(context.Background(), domain.Subscription{ID: "s1", UserID: "u1", ChannelID: "UC_acme"})
+	if err != nil {
+		t.Fatalf("NewVideos: %v", err)
+	}
+	if len(vids) != 1 {
+		t.Fatalf("filter disabled must keep all videos, got %d", len(vids))
+	}
+}
+
+func TestParseISO8601Seconds(t *testing.T) {
+	cases := []struct {
+		in   string
+		want int
+	}{
+		{"PT45S", 45},
+		{"PT1M30S", 90},
+		{"PT3M", 180},
+		{"PT1H2M3S", 3723},
+		{"PT2H", 7200},
+		{"PT0S", 0},
+		{"", 0},
+		{"garbage", 0},
+		{"P1D", 0},  // days component not handled → unknown
+		{"PT10", 0}, // trailing digits without a unit → malformed
+	}
+	for _, c := range cases {
+		if got := parseISO8601Seconds(c.in); got != c.want {
+			t.Errorf("parseISO8601Seconds(%q) = %d, want %d", c.in, got, c.want)
+		}
+	}
+}
+
 // TestUploadsPlaylistID covers the zero-cost UC->UU derivation, including
 // non-standard ids that must fall through unchanged (handled via fallback).
 func TestUploadsPlaylistID(t *testing.T) {

internal/config/config.go

@@ -46,6 +46,12 @@ type Config struct {
 	// MaxTranscriptChars bounds the transcript text sent to the model so a long
 	// transcript does not overflow a small-context primary. 0 disables truncation.
 	MaxTranscriptChars int
+
+	// MinVideoSeconds drops videos shorter than this from discovery (Shorts and
+	// other sub-minute clips that are noise and waste the scarce caption-fetch
+	// budget, ADR-014/ADR-023). Enforced via a cheap Data API videos.list lookup at
+	// discovery, never the rate-limited caption path. 0 disables the filter.
+	MinVideoSeconds int
 	// SummarizerTimeout bounds a single completion call. Thinking models are
 	// slow, so the default is generous.
 	SummarizerTimeout time.Duration
@@ -138,6 +144,7 @@ const (
 	defaultCloudFallbackModel    = "berget/mistral-small"
 	defaultSummaryMaxTokens      = 1500
 	defaultMaxTranscriptChars    = 18000
+	defaultMinVideoSeconds       = 60
 	defaultSummarizerTimeout     = 5 * time.Minute
 	defaultYTTokenRef            = "youtube/refresh_token"
 	defaultYTConnectRedirectURL  = "https://tapir.d-ma.be/oauth/youtube/callback"
@@ -230,6 +237,15 @@ func Load() (Config, error) {
 	}
 	c.MaxTranscriptChars = maxChars
 
+	minVideo, err := intOr("TAPIR_MIN_VIDEO_SECONDS", defaultMinVideoSeconds)
+	if err != nil {
+		return Config{}, err
+	}
+	if minVideo < 0 {
+		minVideo = 0
+	}
+	c.MinVideoSeconds = minVideo
+
 	onboard, err := intOr("TAPIR_ONBOARD_SUMMARIZE_COUNT", defaultOnboardSummarizeCount)
 	if err != nil {
 		return Config{}, err