---
type: reference
description: "The fleet's cloned-voice speech endpoint and the one voice surface consumers address; wired as the harness speech role."
tags:
 - endpoint
 - dankclaw
 - tts
 - voice
 - quadlet
timestamp: 2026-10-19
---

# Frank TTS

`frank-tts` is the fleet's only speech endpoint: an OpenAI-shaped
`POST /v1/audio/speech` on **Dankclaw :7772** that answers `voice=<name>` with
audio in that cloned voice. Everything else in the voice stack sits behind it —
the engine ([[Frank TTS Engine]]) publishes no port on purpose, and consumers
never learn a path.

**Deployed 2026-10-18** — `./scripts/deploy.sh dankclaw --service frank-tts`
both units `active`, no drop-ins, and the homepage card's `wip` gate came off in
the same change. Probes on the deployed endpoint: `/health` answers
`{"status":"ok","backend":"omni-http","voices":["narrator1","narrator2","narrator3"]}`
and two different voices rendered the same sentence into **different** bytes
(24 kHz mono PCM16, 4.24 s, healthy RMS) — so name resolution is real, not a
pass-through of one default. The operator harness routes its `speech` role here;
see [[#The harness speech role]]. What still waits is [[Open Notebook]]: its
render needs the app installed, not this endpoint.

| | |
| --- | --- |
| Host | Dankclaw (`192.168.0.143`), rootless podman, user unit `frank-tts.service` |
| Port | **7772**, published (`PublishPort=7772:7772`) — the rest of the `frank-*` port family is in [[Dankclaw Stack]] |
| Routes | `GET /health`, `GET /v1/audio/voices`, `POST /v1/audio/speech`; everything else 404, and speech is POST-only |
| Image | `localhost/franksdank/frank-tts:latest`, built from `dankclaw/voiceservice/Containerfile`, `Pull=never` |
| Networks | `dankclaw_default` first (it owns the default route and the consumers), then `frank-tts-engine.network` (10.89.5.0/24, the bridge to the engine) |
| Voice packs | `/home/dank/voices` mounted read-only at `/voices` — host state, never repo state |
| Upstream | `http://frank-tts-engine:8880` (`scripts/frank-tts.env`, `TTS_UPSTREAM`) |
| Default voice | `DEFAULT_VOICE` (`scripts/frank-tts.env`) answers a request that names none; the journal marks that line `(default)`, and an **unknown** name is still a 400 |
| Rollback | `TTS_BACKEND=llama-tts-cli` runs a CLI binary per request and needs no upstream at all |

## Naming a voice

A voice **is** a directory name. `voice=narrator1` resolves to
`/voices/narrator1/reference.wav`, and that file — not a manifest, not a config
entry — is what makes the name real. omp's TTS device may send `voice_id`; the
shim accepts either. A call that sends **neither** — the harness's normal shape,
because no harness setting carries a voice for this transport — speaks
`$DEFAULT_VOICE`; empty default makes it a 400 again.

The usable shape is `^[a-z0-9][a-z0-9._-]*$`: lowercase, starting with a letter
or digit, then letters, digits, `.`, `_`, `-`, at most 64 characters. No slash,
no `..`, no space, no uppercase. The lowercase requirement is where two rules
meet: `app.py` would accept `[A-Za-z0-9…]`, but `tts-server` **lowercases
names**, so a pack called `Narrator1` resolves through the façade and not
through the engine. The boot warmer therefore refuses a mixed-case directory
loudly instead of letting it half-work.

Names are user-visible: an unknown voice comes back as
`400 unknown voice 'x'; available voices: …`, and that list is the honest
census. The podcast speakers are `narrator1`, `narrator2`, `narrator3` —
[[Open Notebook]] is configured with exactly those three, so renaming them
breaks episode rendering, not just speech. A personal voice gets the person's
name, lowercase.

## Voice packs

One directory per voice under `/home/dank/voices`:

```
reference.wav    24 kHz mono PCM, 18-25 s of clean single-speaker audio
reference.spk    engine speaker embedding (8 192 B)
reference.rvq    reference codec codes (22 B per 12.5 Hz frame)
manifest.json    source file, offsets, engine, sha256
```

`reference.wav` is the engine-agnostic term the façade gates on; the other two
are what makes a voice reusable by this engine, and they come from the pack
builder ([[Voice Packs]]) — never by hand, never fabricated from the WAV. Two
laws apply to the
source material: offsets always start **past the first 10 seconds** of the
sample, and packs are host state that stays out of this repo. Because the
container runs as uid 10000, files must be world-readable (`644`/`755`), and the
directory must exist before the first deploy: rootless podman auto-creates a
missing bind source **root-owned**, which reads as "no voices" rather than as an
error.

Adding a voice to a running stack is a two-step thing — drop the pack, then
register **and warm** it with
`podman exec frank-tts-engine /app/warm-voices.sh` — because registering alone
does not warm it. The reason is the cold-voice law in [[Frank TTS Engine]], and
the procedure with its proof (the second request under a second) is the
`frank-tts-add-cloned-voice` skill.

## Why the upstream is a container name

`scripts/frank-tts.env` used to point at `http://host.containers.internal:8880`.
That cannot work, and it is the trap this shape exists to avoid: a bridge
container reaches the host's network namespace, netavark DNATs **published**
ports only, and an engine on the host's loopback is published to nobody — the
same shape that 502'd hermes ([[Container Network Namespaces]]). So both units
attach to one committed Quadlet network and the façade dials the engine's
container DNS name.

The consequence worth stating before an operator meets it: **the engine is not
reachable from the host at all** — not over the LAN, not over loopback. Its
health, voice registry and logs are observable only through
`podman exec frank-tts-engine …` and `systemctl --user status`. And the façade's
own `/health` answers 200 with the backend name and the voice list it resolved
without dialing the engine, so "façade healthy, engine down" is a real state: it
shows up as a failed synthesis, never as a down probe.

## Where the engine computes

The **gfx1151 iGPU**, as a co-tenant beside `frank-dragoon`: the Vulkan build of
`qwentts.cpp` with `--device Vulkan0`, and `/dev/dri` handed to the engine container. That is
the shape since 2026-10-19. The flag, the device name, the render-node trap on this hybrid box
and the one-line CPU rollback are owned by [[Frank TTS Engine]] — read that page before
touching either tenant, because a change to one is a change to both. Co-tenancy was gated with
`frank-dragoon` live on the card (its first token and decode rates unchanged with a synthesis
in flight); both gate recipes are §5 of `report/tts-npu-spike-verdict-2026-10-19.md`.

**The Strix Halo NPU is not a door at all**: XDNA2 executes only precompiled AIE partition
programs, and AMD's own Linux runtime opens `/dev/accel/accel0`, succeeds at the ioctls, then
declines this model family's graph without emitting a single log line. The measured record and
the model-side contract live in `report/` at the repo root
(`tts-npu-spike-verdict-2026-10-19.md`).

## Files

| Path | What |
| --- | --- |
| `dankclaw/voiceservice/app.py` | the shim: stdlib only — resolves the voice, forwards, re-encodes mp3 |
| `dankclaw/voiceservice/Containerfile` | python 3.12-alpine pinned by digest + ffmpeg, uid 10000 |
| `dankclaw/voiceservice/quadlet/frank-tts.container` | the unit: two networks, `Restart=always`, `HealthCmd`, `[Install]` |
| `dankclaw/voiceservice/quadlet/frank-tts-engine.network` | the shared bridge, named after the engine unit and attached by both |
| `scripts/frank-tts.env` | backend, upstream, port, limits, and the default voice — paths and numbers, no credentials |
| `tests/frank_tts_unit.bats` | the shim against stub engines over real sockets |
| `tests/frank_tts_engine.bats` | the pair's wiring: generator output, planner, homepage, deployer |

## Deploying it

`./scripts/deploy.sh dankclaw --service frank-tts` (or `--service frank-tts-engine --service frank-tts` for the pair):
builds the façade image, installs **both** Quadlet units — including the
engine's `.network` file, because a referenced `Network=` file the generator
cannot find means the façade unit is not produced at all — creates
`/home/dank/voices` as the deploy user, restarts the unit (whose `Wants=` and
`After=` pull the engine and its warm pass ahead of it) and gates on podman's
recorded health. It never runs `systemctl --user enable`; boot persistence is
the `[Install]` section in each unit. Order matters in a full deploy:
[[Frank TTS Engine]] is planned before this, and both before [[Open Notebook]].

## Not scraped, and why

`shared/prometheus/` gets **no** frank-tts job, and that is a considered
absence. The façade exports no `/metrics` — `app.py` serves `/health` plus the
speech route only — and this Prometheus 3 install refuses non-metrics content
types: [[Prometheus]] records that the existing HTML probes (`comfyui`, the two
`services` targets) sit **down** with
`received unsupported Content-Type … and no fallback_scrape_protocol specified`.
A `/health` probe job would therefore be structurally never-green, and because
`LlmEndpointDown` is scoped across the whole `frank-*` job family (the rule set
lives on [[Prometheus]]), a permanently red `frank-tts` target would page on
Signal every few minutes for an endpoint that is fine. The engine cannot be
scraped at all: it publishes nothing. Status lives in `systemctl --user status`
`podman healthcheck run`, the two unit journals, and the homepage card, which
probes `127.0.0.1:7772` for real now — the `wip: down` gate came off with the
2026-10-18 deploy.

## The harness speech role

The operator harness reaches this endpoint through
`~/.omp/agent/models.yml` — provider `frank-tts (dankclaw)`
`baseUrl: http://192.168.0.143:7772/v1`, `auth: none`, and the runner api
`openai-speech` on the **model** row (naming a runner api at *provider* level
fails the whole file's validation and disables every custom provider, which is
how the fleet's chat endpoints disappear) — plus `config.yml`
`modelRoles.speech: frank-tts (dankclaw)/frank-tts`. Four laws, read out of the
harness bundle and measured the day of the flip:

- **The only voice the harness can send is the `voice_id` argument of the call.**
  The transport builds `{model, input, response_format, voice?}` and adds `voice`
  **only** when the caller passed `voice_id`; no setting feeds it.
  `tts.localVoice` is the *local Kokoro backend's* voice (it is what answered
  `voice=kokoro/bm_george, backend=local` in the control test), and
  `speech.voice` is the TUI's **speak-aloud** voice — its enum is Kokoro's list,
  and it never reaches an HTTP request. So a harness call arrives voice-less by
  default, which is exactly why the endpoint grew `DEFAULT_VOICE`: the declared
  pack answers a voice-less request and the journal marks that line `(default)`
  while an **unknown** name still 400s with the list that exists.
- **`speech.voice` must stay a Kokoro name.** Setting it to a pack name does not
  select a pack; it hands the vocalizer a value outside its enum. (The first
  draft of this section said the opposite and was reverted the same day, after a
  fresh session's call came back `unknown voice None`.)
- **There is no silent fallback.** An explicitly configured `modelRoles.speech`
  yields exactly one candidate, so a dead 7772 fails the speech device with
  *"No available speech model matches the speech role"* instead of quietly
  degrading to Kokoro. That is the price of `auth: none` (which makes a dead
  endpoint read as available) and it is the wanted shape: a narration job should
  fail loudly rather than ship a voice Frank never asked for.
- **A session older than the models.yml row cannot see it.** `models.yml` loads
  at process start while `config.yml` is read live, so a long-lived session
  carrying the flipped role fails exactly like a dead endpoint while a fresh
  process succeeds in the same minute. Measured 2026-10-18: the open session
  failed twice (provider/id form, then the bare id), `local/kokoro` succeeded in
  that same session, and a fresh `omp -p --tools tts` returned `Saved 180524
  bytes (model=frank-tts (dankclaw)/frank-tts, voice=narrator1, codec=wav)`
  while the façade logged the matching `speech voice=narrator1 format=wav
  chars=51 -> 180524 bytes` from the podman bridge. Rule the stale registry out
  before blaming the service.

## Troubleshooting

| Symptom | Cause |
| --- | --- |
| `400 unknown voice 'x'; available voices: …` | the name is not a pack: case, spelling, missing `reference.wav`, or an empty/root-owned `/home/dank/voices` |
| `(none: no voice pack with a reference.wav in /voices)` | the mount, not the voices: `podman inspect frank-tts --format '{{json .Mounts}}'`, then the directory owner |
| Endpoint answers, synthesis fails | the engine: `podman healthcheck run frank-tts-engine`, then `systemctl --user status frank-tts-engine.service` |
| First request of the day is ~0.6 s slower than the rest — or every name returns 400 | the warm pass did not run; it carries `-`, so it cannot fail the unit. `journalctl --user -u frank-tts-engine` for the warmer's lines, then `podman exec frank-tts-engine /app/warm-voices.sh` — the registry is memory-only (law 1 of [[Frank TTS Engine]]) |
| The unit never appears after a deploy | the generator dropped it: `frank-tts-engine.network` is missing from `~/.config/containers/systemd/` |
| A consumer rejects `narrator1` by listing 29 names (`af_heart … bm_fable`) and no request ever reaches this endpoint | that consumer is synthesizing **in the browser** with Kokoro.js, whose voice pack is fixed — OpenWebUI 0.11.4 ships it as the `browser-kokoro` TTS engine; see [[OpenWebUI]] |
---