fix(podcasts): stop late, misattributed podcast generation failures

CHANGELOG.md

@@ -11,8 +11,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **New "Quiet Green" design foundation** — the first of three PRs applying the visual identity co-designed with the community in Discussion #1202. The design token system lands in `globals.css` (core palette, neutral reading surfaces, ink ramp, hairline borders, content-type hues, evidence/citation classes, context-state colors, a squared 4–6px radius scale and a near-flat shadow scale where popovers own the only real shadow); fonts move from Inter to Bricolage Grotesque (display) + Instrument Sans (UI) + Spline Sans Mono (data) via `next/font`; the shadcn primitives are restyled to the foundation's rules (fern green primary actions, red reserved exclusively for destructive/error, clay for warnings, teal as the AI/system voice, underline tabs, quiet neutral badges, teal focus ring); and hard-coded palette colors across 38 components were swept into the semantic tokens, which re-resolve automatically per theme. A dev-only living styleguide at `/dev/design` (404 in production) renders every token and primitive in both themes and serves as the review reference for the follow-up screen-by-screen PRs. Purely visual — no behavior, navigation or i18n changes
 - **Screen-by-screen reskin in the "Quiet Green" language** (the second redesign PR): the app shell gets the recomposed tri-hue pebble wordmark (fern/gold/teal — no red left), a fern spine on the active nav item and destination-hued nav icons; the notebook workspace gets display-type titles, panel headers with identity ticks (sources sage / notes gold / chat teal), one-line source-card metadata with the overflow menu at top-right, and de-washed chat bubbles (the AI speaks in teal accents, never washed backgrounds); the notebooks home separates compact recently-viewed rows from active-notebook cards; the sources table gets the library treatment (content-type pebbles, quiet embedded pills, hover that raises the surface); dialogs and the source viewer are flattened (no card-in-card boxes, uniform breathing room, no ⋮/close collision); and Models/Settings/Podcasts/Transformations/Ask-Search get the badge diet, quiet audio-player containers, mono for data and teal AI accents. Still purely visual — no behavior, columns, navigation or i18n changes
 
+### Fixed
+- **Podcast episode profiles honor their `language` again.** The app's `prompts/podcast/{outline,transcript}.jinja` shadow podcast-creator's bundled templates (the library resolves `Path.cwd()/prompts/podcast/` before its own resources) and had lost the `{{ language }}` block, so a profile set to `he-IL` produced an English outline and English segment titles — the field looked supported and did nothing. A regression test now fails when a variable the bundled template uses is missing from the app's copy (#1238)
+- **A copied prompt placeholder no longer aborts a podcast mid-generation.** Both podcast templates showed the model a fill-in JSON skeleton (`"speaker": "[Actual Speaker Name]"`, a bare `...`) inside a ```json fence while also instructing it not to use fences; models returned the skeleton verbatim, which failed podcast-creator's speaker-name validation and discarded the outline and every segment already generated. The examples are now rendered from the episode's real speaker names (so a verbatim copy is valid output), placeholders and truncation are banned explicitly, and the contradictory fences and second copyable example are gone (#1238)
+- **A speaker voice that the TTS model can't use now fails immediately instead of after the whole transcript.** Audio is generated last, so the profiles seeded on install — which carry OpenAI voice names (`nova`, `echo`, `shimmer`, …) — died on a Gemini voice model with `Google API error: Requested entity was not found.`, which reads like a missing model, once the full transcript had already been generated and paid for. Generation now pre-flights each speaker's voice (including per-speaker `voice_model` overrides) against the provider's voice catalogue and names the offending voice and the valid ones. Only voices that demonstrably belong to another provider fail the run; unknown voices are logged and allowed through, since provider catalogues can be out of date (#1238)
+
 ### Changed
 - Community contribution intake now separates exploration from execution: feature requests, product/design/architecture ideas and contribution proposals start in GitHub Discussions, while Issues are reserved for reproducible bugs and maintainer-approved work items. The Issue chooser routes contributors accordingly, a structured Ideas Discussion form starts from user goals and outcomes, and the contributor/maintainer docs plus PR template now describe the Discussion → Issue → PR graduation path (#1204).
+- Podcast generation failures now carry a hint that matches the failure: a placeholder/renamed speaker name, a `voice_id` its TTS model doesn't support, and a response that was truncated rather than swallowed by `<think>` tags each get their own explanation. The GPT-5 extended-thinking note used to be the only hint, so the two most common real failures got either nothing or advice about the wrong provider (#1238)
 - Release image gate gained a `probe` scenario (`make release-test` runs it as part of `all`): container-level checks that a Python test suite can't cover because they depend on the shipped image's process supervision — `OPEN_NOTEBOOK_WORKER_MAX_TASKS` reaching the in-image worker (the supervisord `sh -c` expansion), and the worker surviving startup with `HTTP_PROXY` set while a user's `NO_PROXY` value is preserved (the internal SurrealDB websocket not being tunneled). Both were manual probes during the v1.14.0 release; they now run automatically. Release-process docs gained the post-tag re-cut sequence and a note on never leaving the version bump uncommitted (v1.14.0 retro)
 
 ## [1.14.0] - 2026-07-20

commands/podcast_commands.py

@@ -41,6 +41,49 @@ def build_episode_output_dir(podcasts_folder: str = PODCASTS_FOLDER) -> tuple[st
     return episode_dir_name, output_dir
 
 
+def explain_generation_failure(error_msg: str) -> Optional[str]:
+    """Map a podcast-generation failure to an actionable hint, or None.
+
+    Ordered most specific first. The GPT-5 extended-thinking hint used to be
+    the only one, so the two most common real failures got either nothing
+    (`Invalid speaker name`) or advice about the wrong provider - a truncated
+    Gemini response was told to switch to gpt-4o (#1238).
+    """
+    if "Invalid speaker name" in error_msg:
+        return (
+            "The transcript model returned a speaker name that is not in the "
+            "speaker profile - usually a placeholder copied from the prompt "
+            'such as "..." rather than an invented person. Speaker names must '
+            "match the profile exactly. Retrying the episode often succeeds, "
+            "since each attempt is a fresh sample."
+        )
+
+    if "Requested entity was not found" in error_msg or (
+        "Voice name" in error_msg and "not supported" in error_msg
+    ):
+        return (
+            "The speaker profile's voice_id is not valid for its TTS model - "
+            "Google returns 'Requested entity was not found' for an unknown "
+            "voice, which reads like a missing model. Check the voices in "
+            "Settings -> Speaker Profiles against the ones your voice model "
+            "provides (the profiles seeded on install use OpenAI voice names)."
+        )
+
+    if "Invalid json output" in error_msg or "Expecting value" in error_msg:
+        return (
+            "The model's response could not be parsed as JSON. Two common "
+            "causes: (1) the response was truncated - podcast-creator caps a "
+            "transcript segment at 5000 output tokens unless the episode "
+            "profile sets max_tokens, which is tight for long segments or "
+            "token-expensive languages, so raise max_tokens or use fewer and "
+            "shorter segments; (2) a model using extended thinking (e.g. "
+            "GPT-5) put all of its output inside <think> tags, leaving nothing "
+            "to parse - try gpt-4o, gpt-4o-mini or gpt-4-turbo instead."
+        )
+
+    return None
+
+
 class PodcastGenerationInput(CommandInput):
     episode_profile: str
     # Speaker profile record ID or name (the API boundary resolves the
@@ -142,6 +185,13 @@ async def generate_podcast_command(
             f"tts: {tts_provider}/{tts_model_name}"
         )
 
+        # Pre-flight the speaker voices against the resolved TTS model. Audio
+        # is generated last, so an unusable voice_id (migration 7 seeds OpenAI
+        # voice names) otherwise fails only after the full transcript has been
+        # generated and paid for, with a provider message that names the wrong
+        # cause: #1238.
+        await speaker_profile.validate_voices()
+
         # 4. Load all profiles and configure podcast-creator
         episode_profiles = await repo_query("SELECT * FROM episode_profile")
         speaker_profiles = await repo_query("SELECT * FROM speaker_profile")
@@ -365,11 +415,8 @@ async def generate_podcast_command(
         logger.exception(e)
 
         error_msg = str(e)
-        if "Invalid json output" in error_msg or "Expecting value" in error_msg:
-            error_msg += (
-                "\n\nNOTE: This error commonly occurs with GPT-5 models that use extended thinking. "
-                "The model may be putting all output inside <think> tags, leaving nothing to parse. "
-                "Try using gpt-4o, gpt-4o-mini, or gpt-4-turbo instead in your episode profile."
-            )
+        hint = explain_generation_failure(error_msg)
+        if hint:
+            error_msg += f"\n\nNOTE: {hint}"
 
         raise RuntimeError(error_msg) from e

docs/7-DEVELOPMENT/podcasts.md

@@ -18,6 +18,22 @@ The legacy string fields (`tts_provider`, `outline_provider`, …) that predated
 
 `PodcastEpisode` stores `episode_profile` and `speaker_profile` as **dicts (snapshots)**, not references. Editing a profile never retroactively changes past episodes — that's intentional. Corollary: deleting a profile does not cascade to episodes.
 
+## Prompt templates shadow podcast-creator's
+
+`prompts/podcast/{outline,transcript}.jinja` are **not** just this app's copies of the library's prompts — they replace them. podcast-creator resolves templates as inline config → `prompts_dir` config → `Path.cwd()/prompts/podcast/<name>.jinja` → its own package resources, and this app configures only profiles, so the working directory wins and the bundled prompts are never read.
+
+Consequences to keep in mind when touching these files:
+
+- Library prompt improvements are invisible here. The `{{ language }}` block was lost exactly this way, which made `EpisodeProfile.language` silently do nothing (#1238). `tests/test_podcast_prompt_templates.py` fails when a variable the bundled template uses is missing from the app's copy.
+- The variables available are whatever `podcast_creator.nodes` passes: the transcript template gets `speaker_names`, the outline template does **not**.
+- Never show the model a fill-in skeleton it can return verbatim. Examples are rendered from the real speaker names so a copied example is still valid output, and placeholders (`...`, `[like this]`) are banned explicitly — a copied `"speaker": "..."` used to abort the whole episode on podcast-creator's speaker-name validation, discarding the segments already generated.
+
+## Voice pre-flight
+
+Audio is generated last, so a `voice_id` the TTS model doesn't accept fails only after the full transcript has been generated and paid for — and the provider message rarely names the voice (Gemini's 3.x TTS preview answers an unknown voice with `404 Requested entity was not found.`). `SpeakerProfile.validate_voices()` runs before generation and checks each speaker's voice (honoring per-speaker `voice_model` overrides) against esperanto's `available_voices` for the resolved model.
+
+It fails the run **only** for a voice another provider's catalogue claims — the case of the migration-7 profiles, seeded with OpenAI voices (`nova`, `echo`, `shimmer`, …), against a Gemini voice model. A voice no catalogue knows is logged and allowed through, because those catalogues go stale (esperanto's OpenAI list predates `ash`), and an unavailable catalogue never blocks generation.
+
 ## Job lifecycle and the retry policy
 
 Generation runs as a `generate_podcast_command` job on the surreal-commands worker:

open_notebook/podcasts/models.py

@@ -183,6 +183,64 @@ async def resolve_tts_config(self) -> Tuple[str, str, dict]:
             )
         return await _resolve_model_config(self.voice_model)
 
+    async def validate_voices(self) -> None:
+        """Reject voice_ids that plainly belong to another TTS provider.
+
+        validate_speakers() can only check that a `voice_id` key exists - it
+        never sees the model, and nothing else checks either. So a profile
+        seeded with OpenAI voices (migration 7) against a Gemini voice_model
+        fails only once the first audio clip is requested - after the whole
+        transcript has been generated and paid for - with a provider message
+        that names the wrong cause (#1238).
+
+        Only certain mismatches raise: a voice missing from the model's
+        catalogue but present in another provider's. A voice no catalogue
+        knows about is logged and allowed through, because esperanto's
+        hard-coded lists go stale (see open_notebook.podcasts.voices). Raises
+        ValueError so the podcast command treats it as permanent (no retry).
+        """
+        from open_notebook.podcasts.voices import find_voice_mismatch, format_voice_list
+
+        profile_tts: Optional[Tuple[str, str, dict]] = None
+        for speaker in self.speakers:
+            override = speaker.get("voice_model")
+            if override:
+                provider, model_name, config = await _resolve_model_config(
+                    str(override)
+                )
+            else:
+                if profile_tts is None:
+                    profile_tts = await self.resolve_tts_config()
+                provider, model_name, config = profile_tts
+
+            voice_id = str(speaker.get("voice_id") or "")
+            mismatch = await find_voice_mismatch(
+                provider, model_name, config, voice_id
+            )
+            if mismatch is None:
+                continue
+
+            valid_voices = format_voice_list(mismatch.known_voices)
+            if not mismatch.confident:
+                logger.warning(
+                    f"Speaker '{speaker.get('name')}' in speaker profile "
+                    f"'{self.name}' uses voice '{voice_id}', which is not in "
+                    f"{provider}/{model_name}'s known voice list "
+                    f"({valid_voices}). Generating anyway - the list may be "
+                    "out of date - but audio generation will fail if the "
+                    "provider rejects it."
+                )
+                continue
+
+            raise ValueError(
+                f"Speaker '{speaker.get('name')}' in speaker profile "
+                f"'{self.name}' uses voice '{voice_id}', which belongs to "
+                f"{', '.join(sorted(mismatch.other_providers))} and is not "
+                f"supported by {provider}/{model_name}. Valid voices: "
+                f"{valid_voices}. Update the voice in Settings -> Speaker "
+                "Profiles, or pick a voice model that provides this voice."
+            )
+
     @classmethod
     async def get_by_name(cls, name: str) -> Optional["SpeakerProfile"]:
         """Get speaker profile by name"""