Fix Lyria silent failures and surface generation status in the player.

Robust candidate-part parsing, quota-aware errors, live composing feedback, and two new desert dub tracks in the library.

Co-authored-by: Cursor <cursoragent@cursor.com>

gateway/player.html

@@ -267,7 +267,10 @@
     font-size: 0.75rem;
     color: var(--muted);
     text-align: center;
+    line-height: 1.4;
   }
+  .status.generating { color: var(--accent); }
+  .status.error { color: #ff5c7a; }
   .stack {
     font-size: 0.7rem;
     color: #555568;
@@ -518,6 +521,7 @@
   let currentTrackId = null;
   let radioSettings = { playback: { shuffle: true, mix_existing_and_new: true, new_song_chance: 0.35 } };
   let savingSettings = false;
+  let lastGenError = null;
 
   function fmtUsd(n) {
     return '$' + Number(n || 0).toFixed(2);
@@ -539,6 +543,34 @@
     loadLibrary();
   }
 
+  function applyGenerationState(gen) {
+    if (!gen) return;
+    if (gen.busy) {
+      genBtn.disabled = true;
+      const title = gen.track_title ? ` "${gen.track_title}"` : '';
+      const phase = gen.phase === 'planning'
+        ? `DeepSeek planning${title}…`
+        : `Lyria composing${title}… (~30s)`;
+      statusEl.textContent = phase;
+      statusEl.classList.add('generating');
+      statusEl.classList.remove('error');
+      return;
+    }
+    genBtn.disabled = false;
+    statusEl.classList.remove('generating');
+    if (gen.error) {
+      statusEl.textContent = gen.error;
+      statusEl.classList.add('error');
+      if (gen.error !== lastGenError) {
+        lastGenError = gen.error;
+        addBubble('dj', `Couldn't finish that track: ${gen.error}`);
+      }
+      return;
+    }
+    lastGenError = null;
+    statusEl.classList.remove('error');
+  }
+
   function updateDashboard(stats) {
     if (!stats) return;
     const today = stats.today || {};
@@ -552,6 +584,7 @@
       radioSettings.playback = stats.playback;
       syncSettingsUI(stats.playback);
     }
+    applyGenerationState(stats.generation);
     updateModeBadge();
   }
 
@@ -568,11 +601,12 @@
     skipBtn.textContent = shuffle ? 'Shuffle next' : 'Skip';
   }
 
-  async function loadStats() {
+  async function loadStats(returnData = false) {
     try {
       const res = await fetch(`${API}/api/stats`);
       const data = await res.json();
       updateDashboard(data);
+      return returnData ? data : undefined;
     } catch (_) {}
   }
 
@@ -704,7 +738,8 @@
       const data = await res.json();
       if (data.reply) addBubble('dj', data.reply);
       if (data.generating) {
-        statusEl.textContent = 'DJ is composing your request…';
+        statusEl.textContent = 'DeepSeek planning your request…';
+        statusEl.classList.add('generating');
         pollForNewTrack();
       }
     } catch (_) {
@@ -722,10 +757,17 @@
     clearInterval(pollTimer);
     pollTimer = setInterval(async () => {
       n += 1;
+      const stats = await loadStats(true);
+      if (stats?.generation?.busy) return;
+      if (stats?.generation?.error) {
+        clearInterval(pollTimer);
+        return;
+      }
       await refreshNow();
-      await loadStats();
+      const now = await fetch(`${API}/api/now`).then(r => r.json()).catch(() => null);
+      if (now?.track?.track_id !== currentTrackId) clearInterval(pollTimer);
       if (n > 60) clearInterval(pollTimer);
-    }, 5000);
+    }, 3000);
   }
 
   async function refreshNow() {
@@ -756,6 +798,10 @@
       } else if (data.status === 'limit') {
         statusEl.textContent = data.message || 'Daily limit reached';
         updateDashboard({ today: data.budget, costs: radioSettings.costs });
+      } else if (data.status === 'error') {
+        statusEl.textContent = data.message || 'Generation failed';
+        statusEl.classList.add('error');
+        applyGenerationState(data.generation || { error: data.message });
       } else if (data.status === 'ok') {
         if (data.track) applyTrack(data.track, data.source || 'generated');
         await loadStats();
@@ -780,8 +826,12 @@
         statusEl.textContent = data.message || 'Daily limit — no more new songs today';
       } else if (data.status === 'busy') {
         statusEl.textContent = data.message;
+        statusEl.classList.add('generating');
         pollForNewTrack();
         return;
+      } else if (data.status === 'error') {
+        statusEl.textContent = data.message || 'Generation failed';
+        statusEl.classList.add('error');
       } else if (data.status === 'ok' && data.track) {
         applyTrack(data.track, data.source);
       } else if (data.status === 'idle') {

songs/82595273.meta.json

@@ -0,0 +1,10 @@
+{
+  "id": "82595273",
+  "title": "Caravan of the Blue Hour",
+  "mood": "hypnotic, warm, spacious",
+  "dj_line": "Late-night dub caravan from the Sahel \u2014 let the bass carry you across the dunes.",
+  "lyria_prompt": "Create a dubtronica track at 90 BPM in A minor. Start with a deep sub bass and a slow, hypnotic stepper beat with rimshot and kick. Add warm analog spring reverb and delay on a muted guitar skank playing offbeat chords. Layer a melancholic kora melody over a djembe pattern with shakers. Introduce a melodica phrase with heavy delay, floating in the stereo field. Keep the arrangement spacious, with filtered breakdowns and echo drops. No vocals. Reference: Thievery Corporation meets Baaba Maal desert warmth.",
+  "lyrics": "[[A0]]\n[[A1]]\n[[A2]]\n[[A3]]\n[[A4]]\n[[A5]]",
+  "file": "82595273_Caravan_of_the_Blue_Hour.mp3",
+  "saved_at": "2026-06-07T13:28:47.487693+00:00"
+}

songs/eeebb429.meta.json

@@ -0,0 +1,10 @@
+{
+  "id": "eeebb429",
+  "title": "Desert Mirage",
+  "mood": "hypnotic, warm, late-night desert dub",
+  "dj_line": "Sending you a dust-kissed groove from the edge of the dunes \u2014 let the delays carry you through the night.",
+  "lyria_prompt": "Instrumental dubtronica track at 92 BPM in D minor. Start with a deep, sub-heavy bassline in a slow stepper rhythm. Layer a clean, plucked kora melody with long, spacey reverb and tape delay. Add a muted guitar skank playing offbeat chords with spring reverb. Hand percussion: djembe and shakers playing a relaxed, syncopated pattern. Introduce a melodica line with heavy echo, floating in the mix. Use analog warmth and subtle vinyl crackle. Build slowly, keeping the arrangement open and spacious. No vocals. Structure: intro with bass and percussion, add kora, then guitar, then melodica, then drop to just bass and percussion before returning with all elements. Fade out with delays.",
+  "lyrics": "[[A0]]\n[[A1]]\n[[A2]]\n[[A3]]\n[[A4]]\n[[A5]]\n[[B6]]",
+  "file": "eeebb429_Desert_Mirage.mp3",
+  "saved_at": "2026-06-07T13:30:41.265970+00:00"
+}

songs/manifest.json

@@ -1,6 +1,6 @@
 {
-  "index": 0,
-  "count": 2,
+  "index": 2,
+  "count": 4,
   "tracks": [
     {
       "id": "b51b1cb2",
@@ -19,6 +19,24 @@
       "lyria_prompt": "A 1-2 minute instrumental track in the style of Sahelian desert blues. Acoustic guitar (kora-like fingerpicking), hand percussion (djembe and calabash), and a warm bass line. Slow-medium tempo (90 BPM), spiritual yet danceable energy. Call-and-response vocal samples woven into the texture, evoking griot traditions. Build from sparse to full, then ease out. No sharp transitions, keep a rolling, hypnotic groove.",
       "lyrics": "[[A0]]\n[[B1]]\n[16.0:] Ah-lay-la, ay-oh... (ay-oh)\n[:] Ah-lay-la, ay-oh... (ay-oh)\n[:] The spirits wake in the morning light,\n[:] Moving through the sand,\n[:] (Moving through the sand).\n[[C2]]\n[48.0:] Oh-lay-ka, ho-lay-ka!\n[:] Oh-lay-ka, ho-lay-ka!\n[:] Feel the heartbeat in the soil!\n[:] Feel the heartbeat in the soil!\n[:] From the river to the dune!\n[:] We are chanting with the sun!\n[:] We are chanting with the sun!\n[[D3]]\n[80.0:] (Mmm-hmmm...)\n[:] (Aaaa-la-ma...)\n[:] (Aaaa-la-ma...)",
       "file": "b548d6a6_Dune_Chant.mp3"
+    },
+    {
+      "id": "82595273",
+      "title": "Caravan of the Blue Hour",
+      "mood": "hypnotic, warm, spacious",
+      "dj_line": "Late-night dub caravan from the Sahel \u2014 let the bass carry you across the dunes.",
+      "lyria_prompt": "Create a dubtronica track at 90 BPM in A minor. Start with a deep sub bass and a slow, hypnotic stepper beat with rimshot and kick. Add warm analog spring reverb and delay on a muted guitar skank playing offbeat chords. Layer a melancholic kora melody over a djembe pattern with shakers. Introduce a melodica phrase with heavy delay, floating in the stereo field. Keep the arrangement spacious, with filtered breakdowns and echo drops. No vocals. Reference: Thievery Corporation meets Baaba Maal desert warmth.",
+      "lyrics": "[[A0]]\n[[A1]]\n[[A2]]\n[[A3]]\n[[A4]]\n[[A5]]",
+      "file": "82595273_Caravan_of_the_Blue_Hour.mp3"
+    },
+    {
+      "id": "eeebb429",
+      "title": "Desert Mirage",
+      "mood": "hypnotic, warm, late-night desert dub",
+      "dj_line": "Sending you a dust-kissed groove from the edge of the dunes \u2014 let the delays carry you through the night.",
+      "lyria_prompt": "Instrumental dubtronica track at 92 BPM in D minor. Start with a deep, sub-heavy bassline in a slow stepper rhythm. Layer a clean, plucked kora melody with long, spacey reverb and tape delay. Add a muted guitar skank playing offbeat chords with spring reverb. Hand percussion: djembe and shakers playing a relaxed, syncopated pattern. Introduce a melodica line with heavy echo, floating in the mix. Use analog warmth and subtle vinyl crackle. Build slowly, keeping the arrangement open and spacious. No vocals. Structure: intro with bass and percussion, add kora, then guitar, then melodica, then drop to just bass and percussion before returning with all elements. Fade out with delays.",
+      "lyrics": "[[A0]]\n[[A1]]\n[[A2]]\n[[A3]]\n[[A4]]\n[[A5]]\n[[B6]]",
+      "file": "eeebb429_Desert_Mirage.mp3"
     }
   ]
 }

src/ozan_radio/lyria.py

@@ -4,6 +4,7 @@ from dataclasses import dataclass
 from pathlib import Path
 
 from google import genai
+from google.genai import errors as genai_errors
 from google.genai import types
 
 from ozan_radio.config import Config
@@ -17,6 +18,49 @@ class GeneratedTrack:
     lyrics: str
 
 
+def friendly_lyria_error(exc: Exception) -> str:
+    """Turn Gemini/Lyria failures into actionable messages (quota, auth, etc.)."""
+    msg = str(exc).lower()
+    if isinstance(exc, genai_errors.ClientError):
+        if any(k in msg for k in ("resource_exhausted", "quota", "rate limit", "429")):
+            return (
+                "Google API quota or credits exhausted — check billing at "
+                "https://aistudio.google.com/apikey"
+            )
+        if any(k in msg for k in ("permission_denied", "403", "invalid api key", "api key")):
+            return "Gemini API key invalid or missing Lyria access"
+        if "billing" in msg or "payment" in msg:
+            return "Google Cloud billing issue — enable billing for Lyria on your project"
+    if isinstance(exc, genai_errors.ServerError):
+        return f"Google Lyria server error — try again in a minute ({exc})"
+    if isinstance(exc, RuntimeError):
+        return str(exc)
+    return f"Lyria generation failed: {exc}"
+
+
+def _response_parts(response) -> list:
+    """SDK sometimes leaves response.parts None; audio lives on candidates."""
+    parts = getattr(response, "parts", None)
+    if parts:
+        return list(parts)
+
+    candidates = getattr(response, "candidates", None) or []
+    if not candidates:
+        feedback = getattr(response, "prompt_feedback", None)
+        if feedback:
+            block = getattr(feedback, "block_reason", None)
+            if block:
+                return []
+        return []
+
+    content = getattr(candidates[0], "content", None)
+    if not content:
+        finish = getattr(candidates[0], "finish_reason", None)
+        raise RuntimeError(f"Lyria returned empty content (finish_reason={finish})")
+
+    return list(getattr(content, "parts", None) or [])
+
+
 class LyriaEngine:
     """Google Lyria 3 — generates tracks from DJ prompts."""
 
@@ -32,25 +76,38 @@ class LyriaEngine:
             "High fidelity, stereo, radio-ready mix."
         )
 
-        response = self._client.models.generate_content(
-            model=self._config.lyria_model,
-            contents=prompt,
-            config=types.GenerateContentConfig(
-                response_modalities=["AUDIO", "TEXT"],
-            ),
-        )
+        try:
+            response = self._client.models.generate_content(
+                model=self._config.lyria_model,
+                contents=prompt,
+                config=types.GenerateContentConfig(
+                    response_modalities=["AUDIO", "TEXT"],
+                ),
+            )
+        except (genai_errors.ClientError, genai_errors.ServerError) as exc:
+            raise RuntimeError(friendly_lyria_error(exc)) from exc
+
+        parts = _response_parts(response)
+        if not parts:
+            raise RuntimeError(
+                "Lyria returned no audio — prompt may have been blocked or the API "
+                "returned an empty response. Not a credits issue if other tracks worked."
+            )
 
         lyrics = ""
         audio_bytes: bytes | None = None
 
-        for part in response.parts:
+        for part in parts:
             if part.text:
                 lyrics += part.text + "\n"
             elif part.inline_data and part.inline_data.data:
                 audio_bytes = part.inline_data.data
 
         if not audio_bytes:
-            raise RuntimeError(f"Lyria returned no audio for track {plan.id}")
+            raise RuntimeError(
+                f"Lyria returned no audio for track {plan.id} — check API quota at "
+                "https://aistudio.google.com/apikey"
+            )
 
         ext = "mp3"
         safe_title = "".join(c if c.isalnum() or c in "-_" else "_" for c in plan.title)[:40]

src/ozan_radio/server.py

@@ -33,6 +33,7 @@ app.add_middleware(
 _config: Config | None = None
 _queue: RadioQueue | None = None
 _generating = False
+_generation_state: dict = {"busy": False, "phase": None, "error": None, "track_title": None}
 _chat = ChatStore()
 
 
@@ -66,6 +67,7 @@ def _dashboard_stats(cfg: Config) -> dict:
         "costs": rs.costs.__dict__ | {"per_track_estimate_usd": per_track},
         "playback": rs.playback.__dict__,
         "projected_daily_max_usd": round(per_track * rs.limits.max_new_songs_per_day, 2),
+        "generation": dict(_generation_state),
     }
 
 
@@ -87,17 +89,29 @@ def _play_library_entry(q: RadioQueue, cfg: Config, entry: dict) -> dict:
     return {"status": "ok", "source": "library", "track": np.__dict__ if np else None}
 
 
+def _set_generation(*, busy: bool, phase: str | None = None, error: str | None = None, title: str | None = None) -> None:
+    global _generation_state
+    _generation_state = {
+        "busy": busy,
+        "phase": phase,
+        "error": error,
+        "track_title": title,
+    }
+
+
 async def _compose_track(request: str | None = None, *, check_limit: bool = True) -> dict:
     global _generating
     if _generating:
-        return {"status": "busy", "message": "Already generating a track"}
+        return {"status": "busy", "message": "Already generating a track", "generation": _generation_state}
 
     _generating = True
+    _set_generation(busy=True, phase="planning", error=None)
     try:
         cfg = _get_config()
         if check_limit:
             ok, budget = _can_generate_today(cfg)
             if not ok:
+                _set_generation(busy=False)
                 return {
                     "status": "limit",
                     "message": f"Daily limit reached ({budget['max_per_day']} new songs)",
@@ -110,6 +124,7 @@ async def _compose_track(request: str | None = None, *, check_limit: bool = True
         plan = await DeepSeekDJ(cfg).plan_next(
             taste, q.recent_titles, seeds, request=vibe or None
         )
+        _set_generation(busy=True, phase="composing", title=plan.title)
         track = LyriaEngine(cfg).generate(plan)
         q.add(track)
         rs = load_radio_settings(lyria_model=cfg.lyria_model)
@@ -117,6 +132,7 @@ async def _compose_track(request: str | None = None, *, check_limit: bool = True
         record_generation(cfg.output_dir, cost, track.plan.id, track.plan.title)
         np = q.now_playing()
         _, budget = _can_generate_today(cfg)
+        _set_generation(busy=False)
         return {
             "status": "ok",
             "source": "generated",
@@ -125,6 +141,10 @@ async def _compose_track(request: str | None = None, *, check_limit: bool = True
             "cost_usd": cost,
             "budget": budget,
         }
+    except Exception as exc:
+        message = str(exc)
+        _set_generation(busy=False, error=message)
+        return {"status": "error", "message": message, "generation": _generation_state}
     finally:
         _generating = False
 
@@ -285,7 +305,7 @@ async def chat_with_dj(body: ChatRequest, background: BackgroundTasks) -> dict:
             ok, _ = _can_generate_today(cfg)
             if ok:
                 result["generating"] = True
-                background.add_task(_compose_track, reply.vibe_hint or None)
+                background.add_task(_background_compose, reply.vibe_hint or None)
             else:
                 result["reply"] += " (Daily new-song limit reached — playing saved tracks only.)"
 
@@ -347,6 +367,13 @@ async def player_page() -> HTMLResponse:
     return HTMLResponse("<h1>Live Ozan Radio</h1><p>gateway/player.html missing</p>")
 
 
+async def _background_compose(request: str | None = None) -> None:
+    """Chat-triggered generation — never raises; errors land in _generation_state."""
+    result = await _compose_track(request)
+    if result.get("status") == "error":
+        _chat.add("dj", f"Couldn't finish that track: {result.get('message', 'unknown error')}")
+
+
 async def _autofill_queue(target: int = 2) -> None:
     """Background: keep a small buffer of generated tracks."""
     while True: