feat(tts): add Azure AI Speech as an optional cloud text-to-speech provider

Neural TTS via the synchronous REST v1 endpoint (SSML body, no token exchange or job polling). Shares one Speech resource with azure_stt — AZURE_SPEECH_KEY + AZURE_SPEECH_REGION unlock both directions; optional AZURE_TTS_ENDPOINT overrides the TTS host (a different subdomain than the STT endpoint). piper_tts remains the default offline path. - tools/audio/azure_tts.py: azure_tts tool (capability=tts), voice shortlist aliases, SSML prosody/style, mp3/wav output, cost tracking - tests/tools/test_azure_tts.py: contract, discovery, status, SSML, and mocked execute tests (21 tests, no live network) - .agents/.claude skills: azure-text-to-speech Layer-3 skill - docs: PROVIDERS.md section + tables, ARCHITECTURE.md inventories, AGENT_GUIDE.md + skills/INDEX.md rows, asset-director TTS cheatsheet, .env.example
2026-08-24 17:10:27 +08:00 · 2026-07-13 20:04:28 +05:30
parent f8d94632ea
commit 888d7b1e72
10 changed files with 831 additions and 12 deletions
--- a/.agents/skills/azure-text-to-speech/SKILL.md
+++ b/.agents/skills/azure-text-to-speech/SKILL.md
@@ -0,0 +1,110 @@
+---
+name: azure-text-to-speech
+description: Generate neural narration audio using Azure AI Speech (REST text-to-speech). Use when synthesizing voiceovers or narration in OpenMontage. Optional cloud TTS provider — preferred when AZURE_SPEECH_KEY is configured; the local piper_tts remains the default offline path. Shares one Speech resource with azure_stt.
+license: MIT
+compatibility: Requires internet access and an Azure AI Speech resource (AZURE_SPEECH_KEY + AZURE_SPEECH_REGION).
+metadata: {"openclaw": {"requires": {"env": ["AZURE_SPEECH_KEY", "AZURE_SPEECH_REGION"]}, "primaryEnv": "AZURE_SPEECH_KEY"}}
+---
+
+# Azure AI Speech — Text-to-Speech
+
+Generate narration with **Azure neural TTS** — high-quality multilingual voices,
+SSML prosody control, and express-as styles, served synchronously by the REST
+`/cognitiveservices/v1` endpoint (no token exchange, Blob storage, or job
+polling). In OpenMontage this is exposed through the `azure_tts` tool
+(`capability=tts`, `provider=azure`). It is an **optional cloud TTS provider** —
+when `AZURE_SPEECH_KEY` is configured, prefer it for high-quality cloud
+narration. The local `piper_tts` remains the **default offline path** and the
+fallback when Azure is unavailable; `elevenlabs_tts` remains the choice for
+voice cloning.
+
+> Docs: [REST text to speech](https://learn.microsoft.com/azure/ai-services/speech-service/rest-text-to-speech) · [Voice gallery](https://speech.microsoft.com/portal/voicegallery)
+
+## Setup
+
+Same Speech resource as `azure_stt` — **one key/region unlocks both directions**
+(STT and TTS). Create a **Speech** resource in the
+[Azure portal](https://portal.azure.com); copy the key and region from its
+**Keys and Endpoint** page.
+
+```bash
+export AZURE_SPEECH_KEY=your_speech_resource_key
+export AZURE_SPEECH_REGION=eastus        # your resource's region
+# export AZURE_TTS_ENDPOINT=https://...  # optional: full custom TTS host
+#   (the TTS host is https://<region>.tts.speech.microsoft.com — a different
+#    subdomain than the STT endpoint, hence the separate override var)
+```
+
+`azure_tts` reports `AVAILABLE` once `AZURE_SPEECH_KEY` plus either
+`AZURE_SPEECH_REGION` or `AZURE_TTS_ENDPOINT` are set.
+
+## Using it in a pipeline
+
+Route through `tts_selector` as usual (it auto-discovers `azure_tts`), or call
+the provider tool directly when the user has approved Azure:
+
+```python
+from tools.tool_registry import registry
+registry.discover()
+tts = registry._tools["azure_tts"]
+
+result = tts.execute({
+    "text": "Every design decision in this dashboard has a reason.",
+    "voice": "andrew",                 # alias or full Azure short name
+    "rate": "-4%",                     # slightly slower for narration
+    # "style": "narration-professional",  # for voices that support styles
+    "output_path": "projects/my-video/assets/audio/seg_001.mp3",
+    "output_format": "mp3",            # or "wav" (48kHz PCM) for mixing
+})
+```
+
+If `azure_tts` is unavailable (no key) or errors, fall back per its declared
+chain: `elevenlabs_tts` → `openai_tts` → `piper_tts`.
+
+## Voice selection
+
+Curated shortlist (aliases accepted by the `voice` param):
+
+| Alias | Voice | Character |
+|-------|-------|-----------|
+| `andrew` | en-US-AndrewMultilingualNeural | warm, confident, conversational — the default; founder/explainer register |
+| `brandon` | en-US-BrandonMultilingualNeural | deeper, measured |
+| `ava` | en-US-AvaMultilingualNeural | confident, bright female |
+| `guy` | en-US-GuyNeural | authoritative |
+| `jenny` | en-US-JennyNeural | friendly, clear |
+
+Any valid Azure voice short name may be passed verbatim (e.g.
+`de-DE-KatjaNeural`); the *Multilingual* voices handle non-English text well —
+set `locale` to match the text's language for correct SSML.
+
+## Parameters that matter
+
+- **`rate` / `pitch`** — SSML prosody. Narration usually reads best slightly
+  slowed (`"-4%"` to `"-8%"`); leave pitch at `"0%"` unless correcting a voice.
+- **`style`** — express-as style for voices that support it
+  (`narration-professional`, `calm`, `newscast`). Unsupported styles are
+  silently ignored by Azure, so listen to a sample before batch runs.
+- **`output_format`** — `mp3` (48kHz/192kbit) for delivery, `wav` (48kHz PCM)
+  when the segment feeds `audio_mixer` for further processing.
+- Determinism: a fixed voice + SSML re-renders effectively identical audio —
+  safe to regenerate individual segments without re-recording the whole set.
+
+## Cost
+
+Azure neural TTS Standard tier bills roughly **$16 per 1M characters** (~$0.016
+per 1k chars; a 150-word narration segment ≈ $0.015). The tool reports
+per-call `cost_usd` for the cost tracker. See
+[Azure AI Speech pricing](https://azure.microsoft.com/pricing/details/cognitive-services/speech-services/) for current rates.
+
+## Limits & tips
+
+- One `execute` call = one narration segment. Generate per script section (the
+  asset stage convention) rather than one giant paragraph — smaller segments
+  align cleanly to scene timings and are cheap to regenerate.
+- The synchronous endpoint caps a request at 10 minutes of audio — far above
+  any segment OpenMontage generates.
+- Text is XML-escaped automatically; do not pre-escape or wrap in SSML — pass
+  plain text plus the `rate`/`pitch`/`style` params.
+- Verify quality: listen to the first generated segment before batch-running a
+  full script (voice/style fit is a creative decision — surface it at the
+  proposal stage per the Decision Communication Contract).
--- a/.claude/skills/azure-text-to-speech/SKILL.md
+++ b/.claude/skills/azure-text-to-speech/SKILL.md
@@ -0,0 +1,110 @@
+---
+name: azure-text-to-speech
+description: Generate neural narration audio using Azure AI Speech (REST text-to-speech). Use when synthesizing voiceovers or narration in OpenMontage. Optional cloud TTS provider — preferred when AZURE_SPEECH_KEY is configured; the local piper_tts remains the default offline path. Shares one Speech resource with azure_stt.
+license: MIT
+compatibility: Requires internet access and an Azure AI Speech resource (AZURE_SPEECH_KEY + AZURE_SPEECH_REGION).
+metadata: {"openclaw": {"requires": {"env": ["AZURE_SPEECH_KEY", "AZURE_SPEECH_REGION"]}, "primaryEnv": "AZURE_SPEECH_KEY"}}
+---
+
+# Azure AI Speech — Text-to-Speech
+
+Generate narration with **Azure neural TTS** — high-quality multilingual voices,
+SSML prosody control, and express-as styles, served synchronously by the REST
+`/cognitiveservices/v1` endpoint (no token exchange, Blob storage, or job
+polling). In OpenMontage this is exposed through the `azure_tts` tool
+(`capability=tts`, `provider=azure`). It is an **optional cloud TTS provider** —
+when `AZURE_SPEECH_KEY` is configured, prefer it for high-quality cloud
+narration. The local `piper_tts` remains the **default offline path** and the
+fallback when Azure is unavailable; `elevenlabs_tts` remains the choice for
+voice cloning.
+
+> Docs: [REST text to speech](https://learn.microsoft.com/azure/ai-services/speech-service/rest-text-to-speech) · [Voice gallery](https://speech.microsoft.com/portal/voicegallery)
+
+## Setup
+
+Same Speech resource as `azure_stt` — **one key/region unlocks both directions**
+(STT and TTS). Create a **Speech** resource in the
+[Azure portal](https://portal.azure.com); copy the key and region from its
+**Keys and Endpoint** page.
+
+```bash
+export AZURE_SPEECH_KEY=your_speech_resource_key
+export AZURE_SPEECH_REGION=eastus        # your resource's region
+# export AZURE_TTS_ENDPOINT=https://...  # optional: full custom TTS host
+#   (the TTS host is https://<region>.tts.speech.microsoft.com — a different
+#    subdomain than the STT endpoint, hence the separate override var)
+```
+
+`azure_tts` reports `AVAILABLE` once `AZURE_SPEECH_KEY` plus either
+`AZURE_SPEECH_REGION` or `AZURE_TTS_ENDPOINT` are set.
+
+## Using it in a pipeline
+
+Route through `tts_selector` as usual (it auto-discovers `azure_tts`), or call
+the provider tool directly when the user has approved Azure:
+
+```python
+from tools.tool_registry import registry
+registry.discover()
+tts = registry._tools["azure_tts"]
+
+result = tts.execute({
+    "text": "Every design decision in this dashboard has a reason.",
+    "voice": "andrew",                 # alias or full Azure short name
+    "rate": "-4%",                     # slightly slower for narration
+    # "style": "narration-professional",  # for voices that support styles
+    "output_path": "projects/my-video/assets/audio/seg_001.mp3",
+    "output_format": "mp3",            # or "wav" (48kHz PCM) for mixing
+})
+```
+
+If `azure_tts` is unavailable (no key) or errors, fall back per its declared
+chain: `elevenlabs_tts` → `openai_tts` → `piper_tts`.
+
+## Voice selection
+
+Curated shortlist (aliases accepted by the `voice` param):
+
+| Alias | Voice | Character |
+|-------|-------|-----------|
+| `andrew` | en-US-AndrewMultilingualNeural | warm, confident, conversational — the default; founder/explainer register |
+| `brandon` | en-US-BrandonMultilingualNeural | deeper, measured |
+| `ava` | en-US-AvaMultilingualNeural | confident, bright female |
+| `guy` | en-US-GuyNeural | authoritative |
+| `jenny` | en-US-JennyNeural | friendly, clear |
+
+Any valid Azure voice short name may be passed verbatim (e.g.
+`de-DE-KatjaNeural`); the *Multilingual* voices handle non-English text well —
+set `locale` to match the text's language for correct SSML.
+
+## Parameters that matter
+
+- **`rate` / `pitch`** — SSML prosody. Narration usually reads best slightly
+  slowed (`"-4%"` to `"-8%"`); leave pitch at `"0%"` unless correcting a voice.
+- **`style`** — express-as style for voices that support it
+  (`narration-professional`, `calm`, `newscast`). Unsupported styles are
+  silently ignored by Azure, so listen to a sample before batch runs.
+- **`output_format`** — `mp3` (48kHz/192kbit) for delivery, `wav` (48kHz PCM)
+  when the segment feeds `audio_mixer` for further processing.
+- Determinism: a fixed voice + SSML re-renders effectively identical audio —
+  safe to regenerate individual segments without re-recording the whole set.
+
+## Cost
+
+Azure neural TTS Standard tier bills roughly **$16 per 1M characters** (~$0.016
+per 1k chars; a 150-word narration segment ≈ $0.015). The tool reports
+per-call `cost_usd` for the cost tracker. See
+[Azure AI Speech pricing](https://azure.microsoft.com/pricing/details/cognitive-services/speech-services/) for current rates.
+
+## Limits & tips
+
+- One `execute` call = one narration segment. Generate per script section (the
+  asset stage convention) rather than one giant paragraph — smaller segments
+  align cleanly to scene timings and are cheap to regenerate.
+- The synchronous endpoint caps a request at 10 minutes of audio — far above
+  any segment OpenMontage generates.
+- Text is XML-escaped automatically; do not pre-escape or wrap in SSML — pass
+  plain text plus the `rate`/`pitch`/`style` params.
+- Verify quality: listen to the first generated segment before batch-running a
+  full script (voice/style fit is a creative decision — surface it at the
+  proposal stage per the Decision Communication Contract).
--- a/.env.example
+++ b/.env.example
@@ -61,12 +61,13 @@ UNSPLASH_ACCESS_KEY=         # Unsplash stock images (free developer key)

 # --- Analysis ---
 HF_TOKEN=                    # HuggingFace token — enables speaker diarization in transcriber
-# Speech-to-text: optional Azure AI Speech (Fast Transcription). When set, the
-# agent prefers azure_stt for cloud STT; the local faster-whisper transcriber
-# remains the default offline path.
+# Speech: optional Azure AI Speech. One key/region unlocks both directions —
+# azure_stt (Fast Transcription cloud STT) and azure_tts (neural cloud TTS).
+# The local faster-whisper transcriber / piper_tts remain the default offline paths.
 AZURE_SPEECH_KEY=            # Azure AI Speech resource key ('Keys and Endpoint' page)
 AZURE_SPEECH_REGION=         # Speech resource region, e.g. eastus
-# AZURE_SPEECH_ENDPOINT=     # Optional: full custom endpoint URL (overrides region)
+# AZURE_SPEECH_ENDPOINT=     # Optional: full custom STT endpoint URL (overrides region)
+# AZURE_TTS_ENDPOINT=        # Optional: full custom TTS host (e.g. https://<region>.tts.speech.microsoft.com)

 # --- Avatar (local installs) ---
 # WAV2LIP_PATH=              # Path to cloned Wav2Lip repo (for lip sync)
--- a/AGENT_GUIDE.md
+++ b/AGENT_GUIDE.md
@@ -501,7 +501,7 @@ Three selector tools abstract multi-provider capabilities. **Selectors auto-disc

 | Selector | Routes to | How it discovers |
 |----------|-----------|-----------------|
-| `tts_selector` | All tools with `capability="tts"` (ElevenLabs, Google TTS, OpenAI, Piper) | `registry.get_by_capability("tts")` |
+| `tts_selector` | All tools with `capability="tts"` (ElevenLabs, Google TTS, OpenAI, Piper, Azure) | `registry.get_by_capability("tts")` |
 | `image_selector` | All tools with `capability="image_generation"` (FLUX, Google Imagen, GPT Image, Recraft, etc.) | `registry.get_by_capability("image_generation")` |
 | `video_selector` | All tools with `capability="video_generation"` | `registry.get_by_capability("video_generation")` |

@@ -677,7 +677,7 @@ The `.agents/skills/` directory is large. When you're not coming in through a to
 | **Character animation** | `character-rigging`, `svg-character-animation`, `pose-library-design`, `canvas-procedural-animation`, `character-animation-qa` |
 | **Image generation** | `bfl-api`, `flux-best-practices` |
 | **Video generation** | `seedance-2-0` (preferred premium default — cinematic, trailer, multi-shot, synced audio, lip-sync), `gemini-omni` (conversational video editing, reference tags, timecoded beats), `ai-video-gen`, `ltx2` |
-| **Audio** | `elevenlabs`, `music`, `sound-effects`, `acestep`, `text-to-speech`, `setup-api-key` |
+| **Audio** | `elevenlabs`, `music`, `sound-effects`, `acestep`, `text-to-speech`, `azure-text-to-speech` (optional cloud TTS — tool `azure_tts`, same Speech key as `azure_stt`), `setup-api-key` |
 | **Speech-to-text** | `speech-to-text` (whisper `transcriber` — default, offline), `azure-speech-to-text` (optional cloud STT — tool `azure_stt`, preferred when `AZURE_SPEECH_KEY` is set) |
 | **Avatar / lip-sync** | `avatar-video`, `heygen`, `create-video`, `faceswap`, `video-translate`, `agents` |
 | **Capture** | `playwright-recording` (browser flows), `ffmpeg` (post) |
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -45,7 +45,7 @@ OpenMontage/
 │   ├── tool_registry.py    # Auto-discovery singleton registry
 │   ├── cost_tracker.py     # Budget governance (estimate → reserve → reconcile)
 │   ├── analysis/           # Transcription, scene detection, frame sampling, video understanding
-│   ├── audio/              # TTS (ElevenLabs, OpenAI, Piper), music gen, mixing, enhancement
+│   ├── audio/              # TTS (ElevenLabs, OpenAI, Piper, Azure, Google), music gen, mixing, enhancement
 │   ├── avatar/             # Talking head animation, lip sync
 │   ├── enhancement/        # Upscale, bg removal, face enhance/restore, color grading
 │   ├── graphics/           # Image gen (FLUX, GPT Image, Recraft, local diffusion), stock, diagrams, code snippets, math animation
@@ -150,9 +150,9 @@ Selectors route based on: user preference when explicitly set, then scored ranki

 ### Tool Inventory by Category

-**Analysis (4):** transcriber (WhisperX), scene_detect, frame_sampler, video_understand (CLIP/BLIP-2)
+**Analysis (5):** transcriber (WhisperX), azure_stt, scene_detect, frame_sampler, video_understand (CLIP/BLIP-2)

-**Audio (8):** elevenlabs_tts, google_tts, openai_tts, piper_tts, tts_selector, music_gen, audio_mixer, audio_enhance
+**Audio (9):** elevenlabs_tts, google_tts, openai_tts, piper_tts, azure_tts, tts_selector, music_gen, audio_mixer, audio_enhance

 **Avatar (2):** talking_head (SadTalker/MuseTalk), lip_sync (Wav2Lip)

@@ -383,6 +383,7 @@ All config is validated via Pydantic models in `lib/config_model.py`.
 | Variable | Used By | Purpose |
 |----------|---------|---------|
 | `ELEVENLABS_API_KEY` | elevenlabs_tts, music_gen | TTS, music, sound effects |
+| `AZURE_SPEECH_KEY` + `AZURE_SPEECH_REGION` | azure_stt, azure_tts | Azure AI Speech cloud transcription + neural TTS (one resource, both directions) |
 | `OPENAI_API_KEY` | openai_tts, openai_image | TTS fallback, GPT Image 2 |
 | `XAI_API_KEY` | grok_image, grok_video | Grok image editing/generation, Grok video generation |
 | `FAL_KEY` | flux_image, kling_video, veo_video, minimax_video, recraft_image | fal.ai hosted models (FLUX, Veo, Kling, MiniMax, Recraft) |
--- a/docs/PROVIDERS.md
+++ b/docs/PROVIDERS.md
@@ -44,8 +44,8 @@ DOUBAO_SPEECH_API_KEY=       # Volcengine Doubao Speech TTS (strong Mandarin nar
 DOUBAO_SPEECH_VOICE_TYPE=    # Default Doubao speaker/voice type
 DASHSCOPE_API_KEY=           # Alibaba DashScope (Qwen image gen, TTS, ASR with word timestamps)

-# SPEECH-TO-TEXT (optional cloud transcription; local whisper is the default)
-AZURE_SPEECH_KEY=            # Azure AI Speech — Fast Transcription (word-level timestamps)
+# AZURE AI SPEECH (optional cloud STT + TTS; one key unlocks both directions)
+AZURE_SPEECH_KEY=            # Azure AI Speech — azure_stt (Fast Transcription) + azure_tts (neural narration)
 AZURE_SPEECH_REGION=         # Speech resource region, e.g. eastus

 # MULTI-MODEL GATEWAY (one key, 6+ tools)
@@ -344,6 +344,64 @@ allowance). OpenMontage estimates cost from the transcribed audio duration. See

 ---

+### Azure AI Speech — Text-to-Speech
+
+> **Cloud neural narration.** Azure neural TTS delivers high-quality multilingual voices with SSML prosody control and express-as styles — same Speech resource as `azure_stt`, so one key/region unlocks both directions. Optional: the local `piper_tts` remains the default offline TTS path. When `AZURE_SPEECH_KEY` is set, the agent may prefer `azure_tts` for cloud narration.
+
+**Tools unlocked:** `azure_tts`
+**Env vars:** `AZURE_SPEECH_KEY`, `AZURE_SPEECH_REGION` (or `AZURE_TTS_ENDPOINT`)
+
+#### Setup
+
+Identical to the STT setup above — the same Speech resource key and region work
+for both. If you already configured `azure_stt`, `azure_tts` is available now.
+
+```bash
+AZURE_SPEECH_KEY=your-speech-resource-key
+AZURE_SPEECH_REGION=eastus
+# AZURE_TTS_ENDPOINT=https://<region>.tts.speech.microsoft.com  # optional, overrides region
+```
+
+Note: the TTS host (`<region>.tts.speech.microsoft.com`) differs from the STT
+endpoint, so the optional override var is `AZURE_TTS_ENDPOINT`, not
+`AZURE_SPEECH_ENDPOINT`.
+
+#### API Notes
+
+OpenMontage uses the synchronous REST v1 endpoint with an SSML body — no token
+exchange, Blob storage, or job polling:
+
+```text
+POST https://{region}.tts.speech.microsoft.com/cognitiveservices/v1
+Ocp-Apim-Subscription-Key: ${AZURE_SPEECH_KEY}
+Content-Type: application/ssml+xml
+X-Microsoft-OutputFormat: audio-48khz-192kbitrate-mono-mp3
+```
+
+Voice shortlist aliases: `andrew` (default — warm, confident), `brandon`
+(deeper), `ava` (bright female), `guy` (authoritative), `jenny` (friendly). Any
+Azure voice short name is accepted verbatim. See the `azure-text-to-speech`
+skill for SSML `rate`/`pitch`/`style` guidance.
+
+#### What It Is Best For
+
+- High-quality neural narration on existing Azure credentials
+- Calm, confident explainer / founder-register delivery
+- Multilingual narration via the *Multilingual* voice family
+- Deterministic re-renders (fixed voice + SSML → identical audio)
+
+Not for: fully offline production (use `piper_tts`) or voice cloning (use
+`elevenlabs_tts`).
+
+#### Pricing
+
+Azure neural TTS Standard (S0) bills roughly **$16 per 1M characters** (a free
+F0 tier includes a limited monthly allowance). A 150-word narration segment
+costs about $0.015. OpenMontage estimates cost from character count. See
+[Azure AI Speech pricing](https://azure.microsoft.com/pricing/details/cognitive-services/speech-services/) for current rates.
+
+---
+
 ### Google — TTS + Imagen + Music + Video (Shared Key)

 > **One key, five tools.** Google Cloud TTS has 700+ voices in 50+ languages — the strongest localization option. Imagen 4 generates high-quality images. Google Lyria generates high-quality background music. Gemini Omni Flash supports conversational video editing, and direct Veo generation covers premium short video clips.
@@ -879,6 +937,7 @@ These tools require only FFmpeg or Python packages — no GPU, no API key.
 | **Pexels** | `PEXELS_API_KEY` | `pexels_image`, `pexels_video` | Free |
 | **Pixabay** | `PIXABAY_API_KEY` | `pixabay_image`, `pixabay_video` | Free |
 | **Piper** | — (install only) | `piper_tts` | Free |
+| **Azure AI Speech** | `AZURE_SPEECH_KEY` + `AZURE_SPEECH_REGION` | `azure_stt`, `azure_tts` | Free tier + paid |
 | **Google** | `GOOGLE_API_KEY` (or `GEMINI_API_KEY`) | `google_tts`, `google_imagen`, `google_music`, `gemini_omni_video`, `veo_video` | Free tier (TTS) + paid |
 | **ElevenLabs** | `ELEVENLABS_API_KEY` | `elevenlabs_tts`, `music_gen` | Free tier + paid |
 | **fal.ai** | `FAL_KEY` | `flux_image`, `recraft_image`, `kling_video`, `veo_video`, `minimax_video` | Pay-as-you-go |
@@ -903,7 +962,7 @@ How many providers cover each capability:
 |-----------|----------------|-----------------|--------------|
 | **Image Generation** | FLUX, Kling Official, Grok, Google Imagen, GPT Image 2, Recraft | Local Diffusion | Pexels, Pixabay (stock) |
 | **Video Generation** | Grok, Kling Official, Kling via fal.ai, Runway, Veo, Gemini Omni, Higgsfield, MiniMax, HeyGen | WAN, Hunyuan, CogVideo, LTX | Pexels, Pixabay (stock) |
-| **Text-to-Speech** | ElevenLabs, Google TTS, Kling Official, OpenAI | Piper | Piper, Google free tier, ElevenLabs free tier |
+| **Text-to-Speech** | Azure AI Speech, ElevenLabs, Google TTS, Kling Official, OpenAI | Piper | Piper, Google free tier, ElevenLabs free tier, Azure free tier |
 | **Music Generation** | ElevenLabs, Suno, Google Lyria | — | ElevenLabs free tier |
 | **Post-Production** | — | FFmpeg (compose, stitch, trim, mix, enhance, grade) | All free |
 | **Analysis** | — | WhisperX, Scene Detect, Frame Sampler, CLIP/BLIP-2 | All free |
--- a/skills/INDEX.md
+++ b/skills/INDEX.md
@@ -83,6 +83,7 @@ Key capability families to look for in the output:
 | HyperFrames | `core/hyperframes.md` | HTML/CSS/GSAP composition runtime — kinetic typography, music-to-video, product promos, website capture. Vendored at v0.7.17 (2026-06-27). | `hyperframes` (router) → `hyperframes-core` (contract), `hyperframes-creative` (palette/type/narration), `hyperframes-media` (TTS/BGM/SFX/captions), `hyperframes-animation` (all motion), `hyperframes-cli`, `hyperframes-registry`, `media-use`, `motion-graphics`, `music-to-video` (beats-driven), `website-to-video`, `remotion-to-hyperframes` (migration), `gsap-core`, `gsap-timeline` |
 | WhisperX | `core/whisperx.md` | Transcription with word-level timestamps — default STT (offline, free) | `speech-to-text` |
 | Azure STT | (tool: `azure_stt`) | Optional cloud speech-to-text, word-level timestamps — preferred when `AZURE_SPEECH_KEY` is set | `azure-speech-to-text` |
+| Azure TTS | (tool: `azure_tts`) | Optional cloud neural narration (SSML prosody, express-as styles) — same Speech key as `azure_stt` | `azure-text-to-speech` |
 | Subtitle Sync | `core/subtitle-sync.md` | Subtitle timing and alignment | `remotion-best-practices` |
 | Color Grading | `core/color-grading.md` | FFmpeg color profiles, LUT workflow, accessibility | `ffmpeg` |

--- a/skills/pipelines/explainer/asset-director.md
+++ b/skills/pipelines/explainer/asset-director.md
@@ -93,6 +93,7 @@ For each script section:
   - OpenAI: `instructions` only with `model: "gpt-4o-mini-tts"`; use `response_format` for output format
   - Google TTS: `input_type: "ssml"` when using `<break>` tags, plus `speaking_rate` in `0.25..2.0` and `pitch` in `-20..20`
   - ElevenLabs: `stability`, `similarity_boost`, `style`, `speed`, and `use_speaker_boost`
+   - Azure: voice aliases (`andrew`, `brandon`, `ava`, `guy`, `jenny`) or any Azure short name, SSML `rate` (e.g. `"-4%"`), `pitch` (e.g. `"+1st"`), and `style` (e.g. `"narration-professional"`) — see the `azure-text-to-speech` skill
 7. Generate using `tts_selector` — it auto-routes to the best available TTS provider based on user preference and availability. Check the registry's `best_for` fields to understand each provider's strengths.
 8. Record the applied `voice_performance` metadata on each narration asset
 9. Verify the audio file exists and duration matches expected timing (±15%)
--- a/tests/tools/test_azure_tts.py
+++ b/tests/tools/test_azure_tts.py
@@ -0,0 +1,247 @@
+"""Focused tests for the Azure AI Speech neural TTS tool.
+
+No live API calls: the network layer is monkeypatched. Covers the tool
+contract, registry discovery, status behavior, voice resolution, SSML
+construction, and execute() guardrails.
+"""
+
+import sys
+from pathlib import Path
+
+import pytest
+
+PROJECT_ROOT = Path(__file__).resolve().parent.parent.parent
+sys.path.insert(0, str(PROJECT_ROOT))
+
+from tools.base_tool import BaseTool, ToolStatus, ToolTier, ToolRuntime
+from tools.tool_registry import ToolRegistry
+from tools.audio.azure_tts import AzureTTS
+
+
+FAKE_MP3 = b"\xff\xfb\x90\x00" + b"\x00" * 64
+
+
+class _FakeResponse:
+    def __init__(self, content=FAKE_MP3, status_code=200, text=""):
+        self.content = content
+        self.status_code = status_code
+        self.text = text
+
+
+@pytest.fixture
+def azure_env(monkeypatch):
+    monkeypatch.setenv("AZURE_SPEECH_KEY", "fake-key")
+    monkeypatch.setenv("AZURE_SPEECH_REGION", "eastus")
+    monkeypatch.delenv("AZURE_TTS_ENDPOINT", raising=False)
+
+
+# ---- Contract ----
+
+class TestContract:
+    def test_inherits_base_tool(self):
+        assert issubclass(AzureTTS, BaseTool)
+
+    def test_identity(self):
+        t = AzureTTS()
+        assert t.name == "azure_tts"
+        assert t.capability == "tts"
+        assert t.provider == "azure"
+        assert t.runtime == ToolRuntime.API
+        assert t.tier == ToolTier.VOICE
+        assert t.fallback == "piper_tts"
+        assert "azure-text-to-speech" in t.agent_skills
+        assert len(t.capabilities) > 0
+
+    def test_get_info_valid(self):
+        info = AzureTTS().get_info()
+        assert info["name"] == "azure_tts"
+        assert info["capability"] == "tts"
+        assert "text" in info["input_schema"]["properties"]
+
+    def test_estimate_cost_by_characters(self):
+        t = AzureTTS()
+        # Standard tier ≈ $16 per 1M characters.
+        assert t.estimate_cost({"text": "x" * 1_000_000}) == pytest.approx(16.0)
+        assert t.estimate_cost({}) == 0.0
+
+
+# ---- Registry discovery ----
+
+class TestDiscovery:
+    def test_discoverable(self):
+        reg = ToolRegistry()
+        reg.discover("tools")
+        assert reg.get("azure_tts") is not None
+
+    def test_capability_routing(self):
+        reg = ToolRegistry()
+        reg.discover("tools")
+        names = [t.name for t in reg.get_by_capability("tts")]
+        assert "azure_tts" in names
+
+
+# ---- Status behavior ----
+
+class TestStatus:
+    def test_unavailable_without_env(self, monkeypatch):
+        monkeypatch.delenv("AZURE_SPEECH_KEY", raising=False)
+        monkeypatch.delenv("AZURE_SPEECH_REGION", raising=False)
+        monkeypatch.delenv("AZURE_TTS_ENDPOINT", raising=False)
+        assert AzureTTS().get_status() == ToolStatus.UNAVAILABLE
+
+    def test_available_with_key_and_region(self, azure_env):
+        assert AzureTTS().get_status() == ToolStatus.AVAILABLE
+
+    def test_available_with_key_and_endpoint(self, monkeypatch):
+        monkeypatch.setenv("AZURE_SPEECH_KEY", "fake-key")
+        monkeypatch.delenv("AZURE_SPEECH_REGION", raising=False)
+        monkeypatch.setenv("AZURE_TTS_ENDPOINT", "https://custom.tts.example.com")
+        assert AzureTTS().get_status() == ToolStatus.AVAILABLE
+
+    def test_key_alone_is_not_enough(self, monkeypatch):
+        monkeypatch.setenv("AZURE_SPEECH_KEY", "fake-key")
+        monkeypatch.delenv("AZURE_SPEECH_REGION", raising=False)
+        monkeypatch.delenv("AZURE_TTS_ENDPOINT", raising=False)
+        assert AzureTTS().get_status() == ToolStatus.UNAVAILABLE
+
+
+# ---- Voice resolution + SSML construction (the risky logic) ----
+
+class TestSSML:
+    def test_voice_alias_resolution(self):
+        t = AzureTTS()
+        assert t._resolve_voice({"voice": "andrew"}) == "en-US-AndrewMultilingualNeural"
+        assert t._resolve_voice({"voice": "JENNY"}) == "en-US-JennyNeural"
+        # full short names pass through untouched
+        assert t._resolve_voice({"voice": "de-DE-KatjaNeural"}) == "de-DE-KatjaNeural"
+        # default when omitted or blank
+        assert t._resolve_voice({}) == AzureTTS.DEFAULT_VOICE
+        assert t._resolve_voice({"voice": "  "}) == AzureTTS.DEFAULT_VOICE
+
+    def test_ssml_prosody_and_voice(self):
+        t = AzureTTS()
+        ssml = t._build_ssml(
+            {"text": "Hello world", "rate": "-8%", "pitch": "+1st"},
+            "en-US-AndrewMultilingualNeural",
+        )
+        assert '<voice name="en-US-AndrewMultilingualNeural">' in ssml
+        assert '<prosody rate="-8%" pitch="+1st">Hello world</prosody>' in ssml
+        assert 'xml:lang="en-US"' in ssml
+        assert "<mstts:express-as" not in ssml  # no style requested
+
+    def test_ssml_style_wrapping(self):
+        t = AzureTTS()
+        ssml = t._build_ssml(
+            {"text": "Hi", "style": "narration-professional"}, "en-US-JennyNeural"
+        )
+        assert '<mstts:express-as style="narration-professional">' in ssml
+        assert "</mstts:express-as>" in ssml
+
+    def test_ssml_escapes_xml(self):
+        t = AzureTTS()
+        ssml = t._build_ssml({"text": "Bread & <butter>"}, "en-US-GuyNeural")
+        assert "Bread &amp; &lt;butter&gt;" in ssml
+        assert "<butter>" not in ssml
+
+    def test_ssml_custom_locale(self):
+        t = AzureTTS()
+        ssml = t._build_ssml({"text": "Hallo", "locale": "de-DE"}, "de-DE-KatjaNeural")
+        assert 'xml:lang="de-DE"' in ssml
+
+    def test_host_prefers_explicit_endpoint(self, monkeypatch):
+        monkeypatch.setenv("AZURE_TTS_ENDPOINT", "https://custom.tts.example.com/")
+        assert AzureTTS()._host() == "https://custom.tts.example.com"
+        monkeypatch.delenv("AZURE_TTS_ENDPOINT")
+        monkeypatch.setenv("AZURE_SPEECH_REGION", "westeurope")
+        assert AzureTTS()._host() == "https://westeurope.tts.speech.microsoft.com"
+
+
+# ---- execute() guardrails + mocked success ----
+
+class TestExecute:
+    def test_missing_credentials(self, monkeypatch):
+        monkeypatch.delenv("AZURE_SPEECH_KEY", raising=False)
+        monkeypatch.delenv("AZURE_SPEECH_REGION", raising=False)
+        monkeypatch.delenv("AZURE_TTS_ENDPOINT", raising=False)
+        res = AzureTTS().execute({"text": "hello"})
+        assert not res.success
+        assert "not configured" in res.error.lower()
+
+    def test_success_path_mocked(self, azure_env, tmp_path, monkeypatch):
+        import requests
+
+        captured = {}
+
+        def fake_post(url, headers=None, data=None, timeout=None):
+            captured["url"] = url
+            captured["headers"] = headers
+            captured["body"] = data
+            return _FakeResponse()
+
+        monkeypatch.setattr(requests, "post", fake_post)
+
+        out = tmp_path / "narration.mp3"
+        res = AzureTTS().execute(
+            {"text": "Hello world", "voice": "andrew", "output_path": str(out)}
+        )
+
+        assert res.success
+        assert res.model == "azure-neural-tts:en-US-AndrewMultilingualNeural"
+        assert res.data["provider"] == "azure"
+        assert res.data["voice"] == "en-US-AndrewMultilingualNeural"
+        assert res.data["text_length"] == len("Hello world")
+        # cost is rounded to 4 decimals by estimate_cost
+        assert res.cost_usd == pytest.approx(round(11 * 16.0 / 1_000_000, 4))
+        # audio bytes written to the requested path
+        assert out.read_bytes() == FAKE_MP3
+        assert res.artifacts == [str(out)]
+        # correct endpoint, auth header, and output format used
+        assert captured["url"] == "https://eastus.tts.speech.microsoft.com/cognitiveservices/v1"
+        assert captured["headers"]["Ocp-Apim-Subscription-Key"] == "fake-key"
+        assert captured["headers"]["X-Microsoft-OutputFormat"] == "audio-48khz-192kbitrate-mono-mp3"
+        assert b"Hello world" in captured["body"]
+
+    def test_wav_output_format(self, azure_env, tmp_path, monkeypatch):
+        import requests
+
+        captured = {}
+
+        def fake_post(url, headers=None, data=None, timeout=None):
+            captured["headers"] = headers
+            return _FakeResponse(content=b"RIFF....")
+
+        monkeypatch.setattr(requests, "post", fake_post)
+
+        out = tmp_path / "narration.wav"
+        res = AzureTTS().execute(
+            {"text": "Hi", "output_format": "wav", "output_path": str(out)}
+        )
+        assert res.success
+        assert captured["headers"]["X-Microsoft-OutputFormat"] == "riff-48khz-16bit-mono-pcm"
+        assert out.exists()
+
+    def test_http_error_surfaced(self, azure_env, tmp_path, monkeypatch):
+        import requests
+
+        monkeypatch.setattr(
+            requests, "post",
+            lambda *a, **k: _FakeResponse(content=b"", status_code=401, text="Unauthorized"),
+        )
+        res = AzureTTS().execute(
+            {"text": "hello", "output_path": str(tmp_path / "x.mp3")}
+        )
+        assert not res.success
+        assert "401" in res.error
+
+    def test_request_exception_surfaced(self, azure_env, tmp_path, monkeypatch):
+        import requests
+
+        def boom(*a, **k):
+            raise requests.exceptions.ConnectionError("no route to host")
+
+        monkeypatch.setattr(requests, "post", boom)
+        res = AzureTTS().execute(
+            {"text": "hello", "output_path": str(tmp_path / "x.mp3")}
+        )
+        assert not res.success
+        assert "no route to host" in res.error
--- a/tools/audio/azure_tts.py
+++ b/tools/audio/azure_tts.py
@@ -0,0 +1,289 @@
+"""Azure AI Speech text-to-speech provider tool.
+
+Neural TTS served by Azure AI Speech via the REST v1 endpoint. This is an
+optional cloud TTS provider; when ``AZURE_SPEECH_KEY`` + ``AZURE_SPEECH_REGION``
+are configured the agent may prefer it for high-quality narration, while the
+local ``piper_tts`` tool remains the default offline path.
+
+Shares the same Speech resource credentials as the ``azure_stt`` transcription
+tool (one key/region unlocks both directions). Uses the synchronous
+``/cognitiveservices/v1`` endpoint with an SSML body — no token exchange, Blob
+storage, or job polling required.
+
+Docs: https://learn.microsoft.com/azure/ai-services/speech-service/rest-text-to-speech
+"""
+
+from __future__ import annotations
+
+import os
+import time
+from pathlib import Path
+from typing import Any
+from xml.sax.saxutils import escape
+
+from tools.base_tool import (
+    BaseTool,
+    Determinism,
+    ExecutionMode,
+    ResourceProfile,
+    RetryPolicy,
+    ToolResult,
+    ToolRuntime,
+    ToolStability,
+    ToolStatus,
+    ToolTier,
+)
+
+# Output format tokens keyed by container. Chosen for compositing quality.
+_MP3_FORMAT = "audio-48khz-192kbitrate-mono-mp3"
+_WAV_FORMAT = "riff-48khz-16bit-mono-pcm"
+
+
+class AzureTTS(BaseTool):
+    name = "azure_tts"
+    version = "0.1.0"
+    tier = ToolTier.VOICE
+    capability = "tts"
+    provider = "azure"
+    stability = ToolStability.BETA
+    execution_mode = ExecutionMode.SYNC
+    # Azure neural TTS is effectively deterministic for a fixed voice + SSML.
+    determinism = Determinism.DETERMINISTIC
+    runtime = ToolRuntime.API
+
+    # Availability is decided by get_status() (env var check), mirroring the
+    # azure_stt and elevenlabs_tts provider tools — dependencies stays empty.
+    dependencies = []
+    install_instructions = (
+        "Set your Azure AI Speech credentials (same resource as azure_stt):\n"
+        "  export AZURE_SPEECH_KEY=your_speech_resource_key\n"
+        "  export AZURE_SPEECH_REGION=eastus   # your Speech resource region\n"
+        "Create a Speech resource in the Azure portal "
+        "(https://portal.azure.com) — the key and region are on its "
+        "'Keys and Endpoint' page. Optionally set AZURE_TTS_ENDPOINT to a full "
+        "custom TTS host (e.g. https://<region>.tts.speech.microsoft.com)."
+    )
+    fallback = "piper_tts"
+    fallback_tools = ["elevenlabs_tts", "openai_tts", "piper_tts"]
+    agent_skills = ["azure-text-to-speech", "text-to-speech"]
+
+    capabilities = [
+        "text_to_speech",
+        "voice_selection",
+        "ssml_support",
+        "prosody_control",
+    ]
+    supports = {
+        "voice_cloning": False,
+        "multilingual": True,
+        "offline": False,
+        "native_audio": True,
+    }
+    best_for = [
+        "high-quality neural narration on Azure credentials",
+        "calm, confident explainer / founder-register delivery",
+        "cloud TTS that shares one key with azure_stt",
+    ]
+    not_good_for = [
+        "fully offline production (use piper_tts)",
+        "voice cloning (use elevenlabs_tts)",
+    ]
+
+    # A small curated shortlist of expressive en-US neural voices. Any valid
+    # Azure voice short name may be passed via `voice`.
+    RECOMMENDED_VOICES = {
+        "andrew": "en-US-AndrewMultilingualNeural",  # warm, confident, conversational (founder)
+        "brandon": "en-US-BrandonMultilingualNeural",  # deeper, measured
+        "ava": "en-US-AvaMultilingualNeural",  # confident, bright female
+        "guy": "en-US-GuyNeural",  # authoritative
+        "jenny": "en-US-JennyNeural",  # friendly, clear
+    }
+    DEFAULT_VOICE = "en-US-AndrewMultilingualNeural"
+
+    input_schema = {
+        "type": "object",
+        "required": ["text"],
+        "properties": {
+            "text": {"type": "string", "description": "Text to convert to speech"},
+            "voice": {
+                "type": "string",
+                "description": (
+                    "Azure voice short name (e.g. 'en-US-AndrewMultilingualNeural') "
+                    "or a shortlist alias: andrew, brandon, ava, guy, jenny. "
+                    "Default: en-US-AndrewMultilingualNeural."
+                ),
+            },
+            "rate": {
+                "type": "string",
+                "description": (
+                    "SSML prosody rate, e.g. '-8%', '0%', '+5%', or 'slow'/'medium'. "
+                    "Default '0%'."
+                ),
+                "default": "0%",
+            },
+            "pitch": {
+                "type": "string",
+                "description": "SSML prosody pitch, e.g. '-2st', '0%', '+1st'. Default '0%'.",
+                "default": "0%",
+            },
+            "style": {
+                "type": "string",
+                "description": (
+                    "Optional express-as style for voices that support it "
+                    "(e.g. 'narration-professional', 'calm', 'newscast'). Omit for neutral."
+                ),
+            },
+            "locale": {
+                "type": "string",
+                "default": "en-US",
+                "description": "BCP-47 locale for the SSML <speak> element.",
+            },
+            "output_path": {"type": "string"},
+            "output_format": {
+                "type": "string",
+                "enum": ["mp3", "wav"],
+                "default": "mp3",
+                "description": "Container: 48kHz 192kbit mp3 or 48kHz 16-bit PCM wav.",
+            },
+        },
+    }
+
+    output_schema = {
+        "type": "object",
+        "properties": {
+            "provider": {"type": "string"},
+            "voice": {"type": "string"},
+            "output": {"type": "string"},
+            "format": {"type": "string"},
+            "text_length": {"type": "integer"},
+        },
+    }
+
+    resource_profile = ResourceProfile(
+        cpu_cores=1, ram_mb=256, vram_mb=0, disk_mb=50, network_required=True
+    )
+    retry_policy = RetryPolicy(
+        max_retries=2,
+        retryable_errors=["ConnectionError", "Timeout", "429", "503"],
+    )
+    idempotency_key_fields = ["text", "voice", "rate", "pitch", "style", "output_format"]
+    side_effects = ["writes audio file to output_path", "sends text to Azure AI Speech"]
+    user_visible_verification = ["Listen to generated audio for natural speech quality"]
+
+    # Azure neural TTS Standard tier bills roughly $16 per 1M characters.
+    COST_PER_CHAR = 16.0 / 1_000_000
+
+    def get_status(self) -> ToolStatus:
+        if os.environ.get("AZURE_SPEECH_KEY") and (
+            os.environ.get("AZURE_SPEECH_REGION") or os.environ.get("AZURE_TTS_ENDPOINT")
+        ):
+            return ToolStatus.AVAILABLE
+        return ToolStatus.UNAVAILABLE
+
+    def estimate_cost(self, inputs: dict[str, Any]) -> float:
+        return round(len(inputs.get("text", "")) * self.COST_PER_CHAR, 4)
+
+    def estimate_runtime(self, inputs: dict[str, Any]) -> float:
+        # Well under real-time for typical narration segments.
+        return 10.0
+
+    def _host(self) -> str:
+        endpoint = os.environ.get("AZURE_TTS_ENDPOINT")
+        if endpoint:
+            return endpoint.rstrip("/")
+        region = os.environ.get("AZURE_SPEECH_REGION", "").strip()
+        return f"https://{region}.tts.speech.microsoft.com"
+
+    def _resolve_voice(self, inputs: dict[str, Any]) -> str:
+        voice = (inputs.get("voice") or "").strip()
+        if not voice:
+            return self.DEFAULT_VOICE
+        return self.RECOMMENDED_VOICES.get(voice.lower(), voice)
+
+    def _build_ssml(self, inputs: dict[str, Any], voice: str) -> str:
+        locale = inputs.get("locale", "en-US")
+        rate = inputs.get("rate", "0%")
+        pitch = inputs.get("pitch", "0%")
+        style = inputs.get("style")
+        text = escape(inputs["text"])
+
+        inner = f'<prosody rate="{escape(rate)}" pitch="{escape(pitch)}">{text}</prosody>'
+        if style:
+            inner = (
+                f'<mstts:express-as style="{escape(style)}">{inner}</mstts:express-as>'
+            )
+        return (
+            f'<speak version="1.0" '
+            f'xmlns="http://www.w3.org/2001/10/synthesis" '
+            f'xmlns:mstts="https://www.w3.org/2001/mstts" '
+            f'xml:lang="{locale}">'
+            f'<voice name="{voice}">{inner}</voice></speak>'
+        )
+
+    def execute(self, inputs: dict[str, Any]) -> ToolResult:
+        api_key = os.environ.get("AZURE_SPEECH_KEY")
+        if not api_key or not (
+            os.environ.get("AZURE_SPEECH_REGION") or os.environ.get("AZURE_TTS_ENDPOINT")
+        ):
+            return ToolResult(
+                success=False,
+                error="Azure Speech is not configured. " + self.install_instructions,
+            )
+
+        start = time.time()
+        try:
+            result = self._synthesize(inputs, api_key)
+        except Exception as exc:
+            return ToolResult(success=False, error=f"TTS generation failed: {exc}")
+
+        result.duration_seconds = round(time.time() - start, 2)
+        result.cost_usd = self.estimate_cost(inputs)
+        return result
+
+    def _synthesize(self, inputs: dict[str, Any], api_key: str) -> ToolResult:
+        import requests
+
+        voice = self._resolve_voice(inputs)
+        container = inputs.get("output_format", "mp3")
+        azure_format = _WAV_FORMAT if container == "wav" else _MP3_FORMAT
+        ext = "wav" if container == "wav" else "mp3"
+
+        ssml = self._build_ssml(inputs, voice)
+        url = f"{self._host()}/cognitiveservices/v1"
+        headers = {
+            "Ocp-Apim-Subscription-Key": api_key,
+            "Content-Type": "application/ssml+xml",
+            "X-Microsoft-OutputFormat": azure_format,
+            "User-Agent": "OpenMontage-azure-tts",
+        }
+
+        try:
+            response = requests.post(
+                url, headers=headers, data=ssml.encode("utf-8"), timeout=120
+            )
+        except requests.RequestException as exc:
+            return ToolResult(success=False, error=f"Azure TTS request failed: {exc}")
+
+        if response.status_code != 200:
+            detail = response.text[:500] if response.text else ""
+            return ToolResult(
+                success=False,
+                error=f"Azure TTS returned HTTP {response.status_code}: {detail}",
+            )
+
+        output_path = Path(inputs.get("output_path", f"tts_output.{ext}"))
+        output_path.parent.mkdir(parents=True, exist_ok=True)
+        output_path.write_bytes(response.content)
+
+        return ToolResult(
+            success=True,
+            data={
+                "provider": self.provider,
+                "voice": voice,
+                "text_length": len(inputs["text"]),
+                "output": str(output_path),
+                "format": azure_format,
+            },
+            artifacts=[str(output_path)],
+            model=f"azure-neural-tts:{voice}",
+        )