diff --git a/.gitignore b/.gitignore
index b1c6b9c..279303f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,9 @@ __pycache__/
 .env.local
 !.env.example
 
+# Voice-cloning consent challenge cache (single-use, per-run)
+.consent-challenge.json
+
 # Generated audio / artifacts
 *.mp3
 *.wav
diff --git a/agents/python-recipes.md b/agents/python-recipes.md
index 866ab2a..e31922e 100644
--- a/agents/python-recipes.md
+++ b/agents/python-recipes.md
@@ -21,7 +21,7 @@ name = "audio-python-quickstart"
 version = "0.1.0"
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
 ```
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 320214f..76608fb 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -7,8 +7,8 @@ settings:
 catalogs:
   default:
     '@speechify/api':
-      specifier: 3.0.1
-      version: 3.0.1
+      specifier: 4.0.1
+      version: 4.0.1
     '@types/node':
       specifier: ^22.10.2
       version: 22.20.0
@@ -114,7 +114,7 @@ importers:
     dependencies:
       '@speechify/api':
         specifier: 'catalog:'
-        version: 3.0.1
+        version: 4.0.1
       dotenv:
         specifier: 'catalog:'
         version: 16.6.1
@@ -133,7 +133,7 @@ importers:
     dependencies:
       '@speechify/api':
         specifier: 'catalog:'
-        version: 3.0.1
+        version: 4.0.1
       dotenv:
         specifier: 'catalog:'
         version: 16.6.1
@@ -152,7 +152,7 @@ importers:
     dependencies:
       '@speechify/api':
         specifier: 'catalog:'
-        version: 3.0.1
+        version: 4.0.1
       dotenv:
         specifier: 'catalog:'
         version: 16.6.1
@@ -171,7 +171,7 @@ importers:
     dependencies:
       '@speechify/api':
         specifier: 'catalog:'
-        version: 3.0.1
+        version: 4.0.1
       dotenv:
         specifier: 'catalog:'
         version: 16.6.1
@@ -190,7 +190,7 @@ importers:
     dependencies:
       '@speechify/api':
         specifier: 'catalog:'
-        version: 3.0.1
+        version: 4.0.1
       dotenv:
         specifier: 'catalog:'
         version: 16.6.1
@@ -363,8 +363,8 @@ packages:
     cpu: [x64]
     os: [win32]
 
-  '@speechify/api@3.0.1':
-    resolution: {integrity: sha512-bEqbyvwGW0A/cgq+ZsQJVP3Hm4/0Bm1sniVtPLBh7vDNG2f/YY8y8sweWojoUnhIeIAL6bHBde43+VZLA2MYpA==}
+  '@speechify/api@4.0.1':
+    resolution: {integrity: sha512-OsfZbx4o47kIZ29OmntUj/9J2LYrlntRHfAwZ8uRLCw2gsu5zgQf46yasDgGe9fNgC5XI1+JfJwCweYVs5w+4w==}
     engines: {node: '>=18.0.0'}
 
   '@types/node@22.20.0':
@@ -482,7 +482,7 @@ snapshots:
   '@esbuild/win32-x64@0.28.1':
     optional: true
 
-  '@speechify/api@3.0.1': {}
+  '@speechify/api@4.0.1': {}
 
   '@types/node@22.20.0':
     dependencies:
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index fc5bfcb..449afdc 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -9,7 +9,7 @@ packages:
 # Single source of truth for shared dependency versions.
 # Recipes reference these with "catalog:" instead of pinning their own.
 catalog:
-  "@speechify/api": 3.0.1
+  "@speechify/api": 4.0.1
   tsx: ^4.19.2
   typescript: ^5.7.2
   "@types/node": ^22.10.2
diff --git a/recipes/audio/python/sdk/quickstart/pyproject.toml b/recipes/audio/python/sdk/quickstart/pyproject.toml
index 95f77ba..095d413 100644
--- a/recipes/audio/python/sdk/quickstart/pyproject.toml
+++ b/recipes/audio/python/sdk/quickstart/pyproject.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 description = "Synthesize speech to an MP3 file with the Speechify TTS API."
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
diff --git a/recipes/audio/python/sdk/quickstart/uv.lock b/recipes/audio/python/sdk/quickstart/uv.lock
index da30115..d8c59d6 100644
--- a/recipes/audio/python/sdk/quickstart/uv.lock
+++ b/recipes/audio/python/sdk/quickstart/uv.lock
@@ -37,7 +37,7 @@ dependencies = [
 [package.metadata]
 requires-dist = [
     { name = "python-dotenv", specifier = ">=1.0.0" },
-    { name = "speechify-api", specifier = ">=3.0.1" },
+    { name = "speechify-api", specifier = ">=4.0.0" },
 ]
 
 [[package]]
@@ -249,7 +249,7 @@ wheels = [
 
 [[package]]
 name = "speechify-api"
-version = "3.0.1"
+version = "4.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "pydantic-core" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/67/961acfbf3355c73b85c9a85e7d2ca4c38a9f14261c845ba9c804940969de/speechify_api-3.0.1.tar.gz", hash = "sha256:e73a084fd6845cb2f92bff2e4dfa6d58052ff97e8112b38dc67ebbf47610aa1a", size = 48230, upload-time = "2026-07-10T19:41:34.679Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/90/3c/4cef771d24e89577b5819b12b351434deb3b5bfd647c21c57c5ece6b2935/speechify_api-4.0.0.tar.gz", hash = "sha256:461ca9f3b6ec3f95a604f299c59152c46bda594a441570a80a4f04d88657f11e", size = 66631, upload-time = "2026-08-18T18:39:42.634Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/b3/7d/52daedb2aa7e1df49f39a03b0d87ea25cd281588102f4231cffbcbf32038/speechify_api-3.0.1-py3-none-any.whl", hash = "sha256:7e09d09bee792a348a5dbfe0e07a806152ba2797c70b399b6e5544b320808cf8", size = 75381, upload-time = "2026-07-10T19:41:33.749Z" },
+    { url = "https://files.pythonhosted.org/packages/fd/70/b783459bd5729da204dfd077301a7a85399a5ccd0e3bb53c655ef421e600/speechify_api-4.0.0-py3-none-any.whl", hash = "sha256:0d811377a4a2a20eeca3c3f443b7853a379df1a8d9fa859f264f8d70b8fd36f0", size = 103832, upload-time = "2026-08-18T18:39:41.424Z" },
 ]
 
 [[package]]
diff --git a/recipes/audio/python/sdk/speech-marks/pyproject.toml b/recipes/audio/python/sdk/speech-marks/pyproject.toml
index a208a9f..64f007b 100644
--- a/recipes/audio/python/sdk/speech-marks/pyproject.toml
+++ b/recipes/audio/python/sdk/speech-marks/pyproject.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 description = "Generate WebVTT captions from word-level speech marks with the Speechify TTS API."
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
diff --git a/recipes/audio/python/sdk/speech-marks/uv.lock b/recipes/audio/python/sdk/speech-marks/uv.lock
index 9e4a77b..53c0c7a 100644
--- a/recipes/audio/python/sdk/speech-marks/uv.lock
+++ b/recipes/audio/python/sdk/speech-marks/uv.lock
@@ -37,7 +37,7 @@ dependencies = [
 [package.metadata]
 requires-dist = [
     { name = "python-dotenv", specifier = ">=1.0.0" },
-    { name = "speechify-api", specifier = ">=3.0.1" },
+    { name = "speechify-api", specifier = ">=4.0.0" },
 ]
 
 [[package]]
@@ -249,7 +249,7 @@ wheels = [
 
 [[package]]
 name = "speechify-api"
-version = "3.0.1"
+version = "4.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "pydantic-core" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/67/961acfbf3355c73b85c9a85e7d2ca4c38a9f14261c845ba9c804940969de/speechify_api-3.0.1.tar.gz", hash = "sha256:e73a084fd6845cb2f92bff2e4dfa6d58052ff97e8112b38dc67ebbf47610aa1a", size = 48230, upload-time = "2026-07-10T19:41:34.679Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/90/3c/4cef771d24e89577b5819b12b351434deb3b5bfd647c21c57c5ece6b2935/speechify_api-4.0.0.tar.gz", hash = "sha256:461ca9f3b6ec3f95a604f299c59152c46bda594a441570a80a4f04d88657f11e", size = 66631, upload-time = "2026-08-18T18:39:42.634Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/b3/7d/52daedb2aa7e1df49f39a03b0d87ea25cd281588102f4231cffbcbf32038/speechify_api-3.0.1-py3-none-any.whl", hash = "sha256:7e09d09bee792a348a5dbfe0e07a806152ba2797c70b399b6e5544b320808cf8", size = 75381, upload-time = "2026-07-10T19:41:33.749Z" },
+    { url = "https://files.pythonhosted.org/packages/fd/70/b783459bd5729da204dfd077301a7a85399a5ccd0e3bb53c655ef421e600/speechify_api-4.0.0-py3-none-any.whl", hash = "sha256:0d811377a4a2a20eeca3c3f443b7853a379df1a8d9fa859f264f8d70b8fd36f0", size = 103832, upload-time = "2026-08-18T18:39:41.424Z" },
 ]
 
 [[package]]
diff --git a/recipes/audio/python/sdk/ssml-emotion/pyproject.toml b/recipes/audio/python/sdk/ssml-emotion/pyproject.toml
index 068fdcb..d7317d4 100644
--- a/recipes/audio/python/sdk/ssml-emotion/pyproject.toml
+++ b/recipes/audio/python/sdk/ssml-emotion/pyproject.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 description = "Control emotion, pitch, rate, pauses & emphasis via SSML with the Speechify TTS API."
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
diff --git a/recipes/audio/python/sdk/ssml-emotion/uv.lock b/recipes/audio/python/sdk/ssml-emotion/uv.lock
index c2a7deb..800cb10 100644
--- a/recipes/audio/python/sdk/ssml-emotion/uv.lock
+++ b/recipes/audio/python/sdk/ssml-emotion/uv.lock
@@ -37,7 +37,7 @@ dependencies = [
 [package.metadata]
 requires-dist = [
     { name = "python-dotenv", specifier = ">=1.0.0" },
-    { name = "speechify-api", specifier = ">=3.0.1" },
+    { name = "speechify-api", specifier = ">=4.0.0" },
 ]
 
 [[package]]
@@ -249,7 +249,7 @@ wheels = [
 
 [[package]]
 name = "speechify-api"
-version = "3.0.1"
+version = "4.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "pydantic-core" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/67/961acfbf3355c73b85c9a85e7d2ca4c38a9f14261c845ba9c804940969de/speechify_api-3.0.1.tar.gz", hash = "sha256:e73a084fd6845cb2f92bff2e4dfa6d58052ff97e8112b38dc67ebbf47610aa1a", size = 48230, upload-time = "2026-07-10T19:41:34.679Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/90/3c/4cef771d24e89577b5819b12b351434deb3b5bfd647c21c57c5ece6b2935/speechify_api-4.0.0.tar.gz", hash = "sha256:461ca9f3b6ec3f95a604f299c59152c46bda594a441570a80a4f04d88657f11e", size = 66631, upload-time = "2026-08-18T18:39:42.634Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/b3/7d/52daedb2aa7e1df49f39a03b0d87ea25cd281588102f4231cffbcbf32038/speechify_api-3.0.1-py3-none-any.whl", hash = "sha256:7e09d09bee792a348a5dbfe0e07a806152ba2797c70b399b6e5544b320808cf8", size = 75381, upload-time = "2026-07-10T19:41:33.749Z" },
+    { url = "https://files.pythonhosted.org/packages/fd/70/b783459bd5729da204dfd077301a7a85399a5ccd0e3bb53c655ef421e600/speechify_api-4.0.0-py3-none-any.whl", hash = "sha256:0d811377a4a2a20eeca3c3f443b7853a379df1a8d9fa859f264f8d70b8fd36f0", size = 103832, upload-time = "2026-08-18T18:39:41.424Z" },
 ]
 
 [[package]]
diff --git a/recipes/audio/python/sdk/streaming/pyproject.toml b/recipes/audio/python/sdk/streaming/pyproject.toml
index e88111c..b63b026 100644
--- a/recipes/audio/python/sdk/streaming/pyproject.toml
+++ b/recipes/audio/python/sdk/streaming/pyproject.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 description = "Stream synthesized audio to a file as it is generated with the Speechify TTS API."
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
diff --git a/recipes/audio/python/sdk/streaming/uv.lock b/recipes/audio/python/sdk/streaming/uv.lock
index 392f096..06dafc8 100644
--- a/recipes/audio/python/sdk/streaming/uv.lock
+++ b/recipes/audio/python/sdk/streaming/uv.lock
@@ -37,7 +37,7 @@ dependencies = [
 [package.metadata]
 requires-dist = [
     { name = "python-dotenv", specifier = ">=1.0.0" },
-    { name = "speechify-api", specifier = ">=3.0.1" },
+    { name = "speechify-api", specifier = ">=4.0.0" },
 ]
 
 [[package]]
@@ -249,7 +249,7 @@ wheels = [
 
 [[package]]
 name = "speechify-api"
-version = "3.0.1"
+version = "4.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "pydantic-core" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/67/961acfbf3355c73b85c9a85e7d2ca4c38a9f14261c845ba9c804940969de/speechify_api-3.0.1.tar.gz", hash = "sha256:e73a084fd6845cb2f92bff2e4dfa6d58052ff97e8112b38dc67ebbf47610aa1a", size = 48230, upload-time = "2026-07-10T19:41:34.679Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/90/3c/4cef771d24e89577b5819b12b351434deb3b5bfd647c21c57c5ece6b2935/speechify_api-4.0.0.tar.gz", hash = "sha256:461ca9f3b6ec3f95a604f299c59152c46bda594a441570a80a4f04d88657f11e", size = 66631, upload-time = "2026-08-18T18:39:42.634Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/b3/7d/52daedb2aa7e1df49f39a03b0d87ea25cd281588102f4231cffbcbf32038/speechify_api-3.0.1-py3-none-any.whl", hash = "sha256:7e09d09bee792a348a5dbfe0e07a806152ba2797c70b399b6e5544b320808cf8", size = 75381, upload-time = "2026-07-10T19:41:33.749Z" },
+    { url = "https://files.pythonhosted.org/packages/fd/70/b783459bd5729da204dfd077301a7a85399a5ccd0e3bb53c655ef421e600/speechify_api-4.0.0-py3-none-any.whl", hash = "sha256:0d811377a4a2a20eeca3c3f443b7853a379df1a8d9fa859f264f8d70b8fd36f0", size = 103832, upload-time = "2026-08-18T18:39:41.424Z" },
 ]
 
 [[package]]
diff --git a/recipes/audio/python/sdk/voice-cloning/.env.example b/recipes/audio/python/sdk/voice-cloning/.env.example
index 4cb51e4..cdea4b1 100644
--- a/recipes/audio/python/sdk/voice-cloning/.env.example
+++ b/recipes/audio/python/sdk/voice-cloning/.env.example
@@ -1 +1,11 @@
+# Get a key at https://platform.speechify.ai/api-keys
+# Voice cloning must be enabled on your plan.
 SPEECHIFY_API_KEY=
+
+# Full name of the person consenting to have their voice cloned.
+CONSENT_FULL_NAME=Jane Doe
+
+# Optional — override where the recipe reads the audio from.
+# Defaults to sample.wav and consent.wav in the recipe folder.
+# SAMPLE_PATH=./sample.wav
+# CONSENT_RECORDING_PATH=./consent.wav
diff --git a/recipes/audio/python/sdk/voice-cloning/README.md b/recipes/audio/python/sdk/voice-cloning/README.md
index 1bde1e8..79476f6 100644
--- a/recipes/audio/python/sdk/voice-cloning/README.md
+++ b/recipes/audio/python/sdk/voice-cloning/README.md
@@ -1,7 +1,7 @@
 # Text-to-Speech: voice cloning (Python)
 
 Clone a voice from an audio sample, synthesize speech with the clone, then delete it — the
-full create → use → delete lifecycle.
+full create → use → delete lifecycle, with **verified consent**.
 
 ## Prerequisites
 
@@ -10,6 +10,9 @@ full create → use → delete lifecycle.
   pointing to [Speechify pricing](https://speechify.ai/pricing) (the API returns
   `402 voice_cloning_not_included`).
 - Python 3.10+ and [uv](https://docs.astral.sh/uv/)
+- **Two recordings of the same consenting person** (see [Consent](#consent)):
+  - a voice **sample** to clone — 10–30s of clean speech
+  - a **consent recording** — that person reading the challenge phrase this recipe prints
 
 ## Setup
 
@@ -20,29 +23,41 @@ uv sync
 
 ## Run
 
+Because consent is verified against a phrase the API generates, this is a two-step run:
+
 ```bash
-uv run main.py
+uv run main.py   # 1st run: prints the phrase to read, then exits
+# record the speaker reading that phrase → consent.wav, and their voice → sample.wav
+uv run main.py   # 2nd run: clones, synthesizes, deletes
 ```
 
-Produces an `output.mp3` spoken in the cloned voice, then removes the cloned voice.
+Put `sample.wav` and `consent.wav` in the recipe folder, or point `SAMPLE_PATH` /
+`CONSENT_RECORDING_PATH` at them. Produces an `output.mp3` in the cloned voice, then
+removes the cloned voice.
 
 ## What it does
 
-- `client.voices.create(...)` — clones a voice from `fixtures/spacewalk.wav`. Required
-  fields: `name`, `gender`, `sample` (a readable binary file of 10–30s of clean speech),
-  and `consent`.
+- `client.voices.consent_challenges.create(full_name=...)` — starts a consent challenge and
+  returns a `phrase` the speaker must read aloud (cached in `.consent-challenge.json`
+  between runs; single-use).
+- `client.voices.create(...)` — clones the voice. Required: `name`, `gender`, `sample` (a
+  readable binary file of 10–30s of clean speech), `consent_challenge_id`, and
+  `consent_recording` (the speaker reading the phrase).
 - `client.audio.speech(...)` with `voice_id` set to the new voice's id.
-- `client.voices.delete(id)` — cleans up so personal voices don't accumulate.
+- `client.voices.delete(voice_id)` — cleans up so personal voices don't accumulate.
 
 ## Consent
 
-`consent` is a **required** JSON string attesting you have the speaker's permission to
-clone their voice (`{"fullName": "...", "email": "..."}`). Only clone voices you are
-authorized to. The bundled `fixtures/spacewalk.wav` is ~26s of NASA ISS spacewalk audio
-(U.S. government work, public domain); replace it with your own consented sample for real
-use.
+Cloning requires **verified consent**. You create a consent challenge, the speaker records
+themselves reading the returned `phrase`, and that recording is sent as `consent_recording`
+and retained as the consent record. The `consent_recording` **must be the same person** as
+the voice `sample` — so there is no shippable sample that comes with valid consent, and this
+recipe is deliberately bring-your-own-audio. Only clone voices you are authorized to.
 
+> The old `consent` JSON field (`fullName` + `email`) is removed in SDK 4.x — see the
+> [migration guide](https://docs.speechify.ai/build/guides/deprecations/migrating-voice-cloning-consent).
+>
 > Note: `voices.list()` is eventually consistent — a just-deleted voice may still appear in
 > the list briefly. The delete itself is immediate (a subsequent delete returns 404).
 >
-> Voice cloning reference: https://docs.speechify.ai/tts/guides/voice-cloning
+> Voice cloning reference: https://docs.speechify.ai/build/guides/voice-cloning/overview
diff --git a/recipes/audio/python/sdk/voice-cloning/fixtures/spacewalk.wav b/recipes/audio/python/sdk/voice-cloning/fixtures/spacewalk.wav
deleted file mode 100644
index 498be74..0000000
Binary files a/recipes/audio/python/sdk/voice-cloning/fixtures/spacewalk.wav and /dev/null differ
diff --git a/recipes/audio/python/sdk/voice-cloning/main.py b/recipes/audio/python/sdk/voice-cloning/main.py
index e185fd0..3e58cb9 100644
--- a/recipes/audio/python/sdk/voice-cloning/main.py
+++ b/recipes/audio/python/sdk/voice-cloning/main.py
@@ -1,13 +1,35 @@
 import base64
 import json
 import os
+from datetime import datetime, timezone
 
 from dotenv import load_dotenv
 from speechify import Speechify
 from speechify.core.api_error import ApiError
 
-# Bundled sample: ~26s of NASA ISS spacewalk audio (public domain).
-SAMPLE_PATH = os.path.join(os.path.dirname(__file__), "fixtures", "spacewalk.wav")
+# Cloning requires VERIFIED consent: the speaker records themselves reading a
+# phrase Speechify returns, and that recording is kept as the consent record.
+# It must be the SAME person as the voice sample, so this recipe is
+# bring-your-own-audio — there is no sample that ships with valid consent.
+HERE = os.path.dirname(__file__)
+CONSENT_FULL_NAME = os.environ.get("CONSENT_FULL_NAME", "Jane Doe")
+# The voice to clone (10-30s of clean speech) and the consent recording (the
+# same person reading the challenge phrase, 5-30s). Same speaker in both.
+SAMPLE_PATH = os.environ.get("SAMPLE_PATH", os.path.join(HERE, "sample.wav"))
+CONSENT_RECORDING_PATH = os.environ.get("CONSENT_RECORDING_PATH", os.path.join(HERE, "consent.wav"))
+# The challenge is single-use and its phrase is dynamic, so we cache it between
+# runs: run once to get the phrase, record it, run again to submit.
+CHALLENGE_CACHE = os.path.join(HERE, ".consent-challenge.json")
+
+
+def load_challenge():
+    if not os.path.exists(CHALLENGE_CACHE):
+        return None
+    with open(CHALLENGE_CACHE) as f:
+        c = json.load(f)
+    if datetime.fromisoformat(c["expires_at"]) <= datetime.now(timezone.utc):
+        return None  # expired -> make a fresh one
+    return c
 
 
 def main() -> None:
@@ -19,16 +41,44 @@ def main() -> None:
 
     client = Speechify(token=token)
 
-    # 1. Clone a voice from an audio sample (10-30s of clean speech works well).
-    #    `consent` is REQUIRED: a JSON string attesting you have the speaker's
-    #    permission to clone their voice. Use the real consenting person's details.
+    # 1. Get (or reuse) a consent challenge. Its `phrase` is what the speaker
+    #    must read aloud; `id` ties the recording to this consent on the create.
+    challenge = load_challenge()
+    if challenge is None:
+        created = client.voices.consent_challenges.create(full_name=CONSENT_FULL_NAME)
+        challenge = {
+            "id": created.id,
+            "phrase": created.phrase,
+            "expires_at": created.expires_at.isoformat(),
+        }
+        with open(CHALLENGE_CACHE, "w") as f:
+            json.dump(challenge, f, indent=2)
+
+    # 2. Make sure we have both recordings before spending the (single-use) challenge.
+    missing = []
+    if not os.path.exists(SAMPLE_PATH):
+        missing.append(f"  sample:  {SAMPLE_PATH}  ({CONSENT_FULL_NAME}'s voice, 10-30s of clean speech)")
+    if not os.path.exists(CONSENT_RECORDING_PATH):
+        missing.append(f"  consent: {CONSENT_RECORDING_PATH}  (the SAME person reading the phrase below)")
+    if missing:
+        raise SystemExit(
+            f"\nConsent required. Have {CONSENT_FULL_NAME} record themselves reading this phrase, "
+            "exactly as written:\n\n"
+            f'  "{challenge["phrase"]}"\n\n'
+            "Then provide these files and re-run (paths override via SAMPLE_PATH / CONSENT_RECORDING_PATH):\n"
+            + "\n".join(missing)
+            + f"\n\nChallenge expires {challenge['expires_at']}.\n"
+        )
+
+    # 3. Clone the voice: the sample + the consent recording + the challenge id.
     try:
-        with open(SAMPLE_PATH, "rb") as sample:
+        with open(SAMPLE_PATH, "rb") as sample, open(CONSENT_RECORDING_PATH, "rb") as consent:
             voice = client.voices.create(
                 name="cookbook-cloned-voice",
                 gender="male",
                 sample=sample,
-                consent=json.dumps({"fullName": "Jane Doe", "email": "jane@example.com"}),
+                consent_challenge_id=challenge["id"],
+                consent_recording=consent,
             )
     except ApiError as err:
         # Voice cloning is gated by plan. A 402 means it isn't included in yours.
@@ -38,10 +88,11 @@ def main() -> None:
                 "Upgrade to a plan that includes voice cloning: https://speechify.ai/pricing\n"
             )
         raise
+    os.remove(CHALLENGE_CACHE)  # challenge is spent
     print(f"Cloned voice created: {voice.id} ({voice.display_name}, type={voice.type})")
 
     try:
-        # 2. Synthesize speech using the cloned voice — pass its id as voice_id.
+        # 4. Synthesize speech using the cloned voice — pass its id as voice_id.
         speech = client.audio.speech(
             input="Hello from a voice cloned with the Speechify API.",
             voice_id=voice.id,
@@ -52,7 +103,7 @@ def main() -> None:
             f.write(base64.b64decode(speech.audio_data))
         print("Wrote output.mp3")
     finally:
-        # 3. Clean up so cloned voices don't accumulate on your account.
+        # 5. Clean up so cloned voices don't accumulate on your account.
         #    Remove this to keep the voice and reuse it later via voice.id.
         client.voices.delete(voice.id)
         print(f"Deleted cloned voice {voice.id}")
diff --git a/recipes/audio/python/sdk/voice-cloning/pyproject.toml b/recipes/audio/python/sdk/voice-cloning/pyproject.toml
index 30f972f..f6c3a5c 100644
--- a/recipes/audio/python/sdk/voice-cloning/pyproject.toml
+++ b/recipes/audio/python/sdk/voice-cloning/pyproject.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 description = "Clone a voice from an audio sample, synthesize with it, then delete it (Speechify TTS API)."
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]
diff --git a/recipes/audio/python/sdk/voice-cloning/uv.lock b/recipes/audio/python/sdk/voice-cloning/uv.lock
index 458db63..4a853c2 100644
--- a/recipes/audio/python/sdk/voice-cloning/uv.lock
+++ b/recipes/audio/python/sdk/voice-cloning/uv.lock
@@ -37,7 +37,7 @@ dependencies = [
 [package.metadata]
 requires-dist = [
     { name = "python-dotenv", specifier = ">=1.0.0" },
-    { name = "speechify-api", specifier = ">=3.0.1" },
+    { name = "speechify-api", specifier = ">=4.0.0" },
 ]
 
 [[package]]
@@ -249,7 +249,7 @@ wheels = [
 
 [[package]]
 name = "speechify-api"
-version = "3.0.1"
+version = "4.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "httpx" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "pydantic-core" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/6d/67/961acfbf3355c73b85c9a85e7d2ca4c38a9f14261c845ba9c804940969de/speechify_api-3.0.1.tar.gz", hash = "sha256:e73a084fd6845cb2f92bff2e4dfa6d58052ff97e8112b38dc67ebbf47610aa1a", size = 48230, upload-time = "2026-07-10T19:41:34.679Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/90/3c/4cef771d24e89577b5819b12b351434deb3b5bfd647c21c57c5ece6b2935/speechify_api-4.0.0.tar.gz", hash = "sha256:461ca9f3b6ec3f95a604f299c59152c46bda594a441570a80a4f04d88657f11e", size = 66631, upload-time = "2026-08-18T18:39:42.634Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/b3/7d/52daedb2aa7e1df49f39a03b0d87ea25cd281588102f4231cffbcbf32038/speechify_api-3.0.1-py3-none-any.whl", hash = "sha256:7e09d09bee792a348a5dbfe0e07a806152ba2797c70b399b6e5544b320808cf8", size = 75381, upload-time = "2026-07-10T19:41:33.749Z" },
+    { url = "https://files.pythonhosted.org/packages/fd/70/b783459bd5729da204dfd077301a7a85399a5ccd0e3bb53c655ef421e600/speechify_api-4.0.0-py3-none-any.whl", hash = "sha256:0d811377a4a2a20eeca3c3f443b7853a379df1a8d9fa859f264f8d70b8fd36f0", size = 103832, upload-time = "2026-08-18T18:39:41.424Z" },
 ]
 
 [[package]]
diff --git a/recipes/audio/typescript/sdk/streaming/src/index.ts b/recipes/audio/typescript/sdk/streaming/src/index.ts
index de15b6b..6d8f436 100644
--- a/recipes/audio/typescript/sdk/streaming/src/index.ts
+++ b/recipes/audio/typescript/sdk/streaming/src/index.ts
@@ -16,11 +16,13 @@ async function main() {
   // long inputs.
   const response = await client.audio.stream({
     Accept: "audio/mpeg",
-    input:
-      "Streaming lets you start playing audio before the whole clip is ready. " +
-      "This sentence is being synthesized and written to disk chunk by chunk.",
-    voice_id: "geffen_32",
-    model: "simba-3.2",
+    body: {
+      input:
+        "Streaming lets you start playing audio before the whole clip is ready. " +
+        "This sentence is being synthesized and written to disk chunk by chunk.",
+      voice_id: "geffen_32",
+      model: "simba-3.2",
+    },
   });
 
   const outFile = "output.mp3";
diff --git a/recipes/audio/typescript/sdk/voice-cloning/.env.example b/recipes/audio/typescript/sdk/voice-cloning/.env.example
index 6f5312e..cdea4b1 100644
--- a/recipes/audio/typescript/sdk/voice-cloning/.env.example
+++ b/recipes/audio/typescript/sdk/voice-cloning/.env.example
@@ -1,3 +1,11 @@
 # Get a key at https://platform.speechify.ai/api-keys
 # Voice cloning must be enabled on your plan.
 SPEECHIFY_API_KEY=
+
+# Full name of the person consenting to have their voice cloned.
+CONSENT_FULL_NAME=Jane Doe
+
+# Optional — override where the recipe reads the audio from.
+# Defaults to sample.wav and consent.wav in the recipe folder.
+# SAMPLE_PATH=./sample.wav
+# CONSENT_RECORDING_PATH=./consent.wav
diff --git a/recipes/audio/typescript/sdk/voice-cloning/README.md b/recipes/audio/typescript/sdk/voice-cloning/README.md
index f2988ea..0c0a479 100644
--- a/recipes/audio/typescript/sdk/voice-cloning/README.md
+++ b/recipes/audio/typescript/sdk/voice-cloning/README.md
@@ -1,7 +1,7 @@
 # Text-to-Speech: voice cloning (TypeScript)
 
 Clone a voice from an audio sample, synthesize speech with the clone, then delete it — the
-full create → use → delete lifecycle.
+full create → use → delete lifecycle, with **verified consent**.
 
 ## Prerequisites
 
@@ -10,6 +10,9 @@ full create → use → delete lifecycle.
   pointing to [Speechify pricing](https://speechify.ai/pricing) (the API returns
   `402 voice_cloning_not_included`).
 - Node 20+
+- **Two recordings of the same consenting person** (see [Consent](#consent)):
+  - a voice **sample** to clone — 10–30s of clean speech
+  - a **consent recording** — that person reading the challenge phrase this recipe prints
 
 ## Setup
 
@@ -20,29 +23,41 @@ pnpm install
 
 ## Run
 
+Because consent is verified against a phrase the API generates, this is a two-step run:
+
 ```bash
-pnpm start
+pnpm start   # 1st run: prints the phrase to read, then exits
+# record the speaker reading that phrase → consent.wav, and their voice → sample.wav
+pnpm start   # 2nd run: clones, synthesizes, deletes
 ```
 
-Produces an `output.mp3` spoken in the cloned voice, then removes the cloned voice.
+Put `sample.wav` and `consent.wav` in the recipe folder, or point `SAMPLE_PATH` /
+`CONSENT_RECORDING_PATH` at them. Produces an `output.mp3` in the cloned voice, then
+removes the cloned voice.
 
 ## What it does
 
-- `client.voices.create(...)` — clones a voice from `fixtures/spacewalk.wav`. Required
-  fields: `name`, `gender`, `sample` (a readable stream of 10–30s of clean speech), and
-  `consent`.
+- `client.voices.consentChallenges.create({ full_name })` — starts a consent challenge and
+  returns a `phrase` the speaker must read aloud (cached in `.consent-challenge.json`
+  between runs; single-use).
+- `client.voices.create(...)` — clones the voice. Required: `name`, `gender`, `sample` (a
+  readable stream of 10–30s of clean speech), `consent_challenge_id`, and
+  `consent_recording` (the speaker reading the phrase).
 - `client.audio.speech(...)` with `voice_id` set to the new voice's id.
-- `client.voices.delete({ id })` — cleans up so personal voices don't accumulate.
+- `client.voices.delete({ voice_id })` — cleans up so personal voices don't accumulate.
 
 ## Consent
 
-`consent` is a **required** JSON string attesting you have the speaker's permission to
-clone their voice (`{"fullName": "...", "email": "..."}`). Only clone voices you are
-authorized to. The bundled `fixtures/spacewalk.wav` is ~26s of NASA ISS spacewalk audio
-(U.S. government work, public domain); replace it with your own consented sample for real
-use.
+Cloning requires **verified consent**. You create a consent challenge, the speaker records
+themselves reading the returned `phrase`, and that recording is sent as `consent_recording`
+and retained as the consent record. The `consent_recording` **must be the same person** as
+the voice `sample` — so there is no shippable sample that comes with valid consent, and this
+recipe is deliberately bring-your-own-audio. Only clone voices you are authorized to.
 
+> The old `consent` JSON field (`fullName` + `email`) is removed in SDK 4.x — see the
+> [migration guide](https://docs.speechify.ai/build/guides/deprecations/migrating-voice-cloning-consent).
+>
 > Note: `voices.list()` is eventually consistent — a just-deleted voice may still appear in
 > the list briefly. The delete itself is immediate (a subsequent delete returns 404).
 >
-> Voice cloning reference: https://docs.speechify.ai/tts/guides/voice-cloning
+> Voice cloning reference: https://docs.speechify.ai/build/guides/voice-cloning/overview
diff --git a/recipes/audio/typescript/sdk/voice-cloning/fixtures/spacewalk.wav b/recipes/audio/typescript/sdk/voice-cloning/fixtures/spacewalk.wav
deleted file mode 100644
index 498be74..0000000
Binary files a/recipes/audio/typescript/sdk/voice-cloning/fixtures/spacewalk.wav and /dev/null differ
diff --git a/recipes/audio/typescript/sdk/voice-cloning/src/index.ts b/recipes/audio/typescript/sdk/voice-cloning/src/index.ts
index 2014a6f..d4d98a8 100644
--- a/recipes/audio/typescript/sdk/voice-cloning/src/index.ts
+++ b/recipes/audio/typescript/sdk/voice-cloning/src/index.ts
@@ -9,20 +9,67 @@ if (!process.env.SPEECHIFY_API_KEY) {
 
 const client = new SpeechifyClient({ token: process.env.SPEECHIFY_API_KEY });
 
-// Bundled sample: ~26s of NASA ISS spacewalk audio (public domain).
-const samplePath = path.resolve(import.meta.dirname, "../fixtures/spacewalk.wav");
+// Cloning requires VERIFIED consent: the speaker records themselves reading a
+// phrase Speechify returns, and that recording is kept as the consent record.
+// The recording must be the SAME person as the voice sample. So this recipe is
+// bring-your-own-audio — there is no sample that ships with valid consent.
+const CONSENT_FULL_NAME = process.env.CONSENT_FULL_NAME ?? "Jane Doe";
+const dir = import.meta.dirname;
+// The voice to clone (10–30s of clean speech) and the consent recording (the
+// same person reading the challenge phrase, 5–30s). Same speaker in both.
+const samplePath = path.resolve(process.env.SAMPLE_PATH ?? path.join(dir, "../sample.wav"));
+const consentPath = path.resolve(process.env.CONSENT_RECORDING_PATH ?? path.join(dir, "../consent.wav"));
+// The challenge is single-use and its phrase is dynamic, so we cache it between
+// runs: run once to get the phrase, record it, run again to submit.
+const challengeCache = path.join(dir, "../.consent-challenge.json");
+
+interface CachedChallenge {
+  id: string;
+  phrase: string;
+  expires_at: string;
+}
+
+function loadChallenge(): CachedChallenge | null {
+  if (!fs.existsSync(challengeCache)) return null;
+  const c = JSON.parse(fs.readFileSync(challengeCache, "utf8")) as CachedChallenge;
+  if (new Date(c.expires_at).getTime() <= Date.now()) return null; // expired → make a fresh one
+  return c;
+}
 
 async function main() {
-  // 1. Clone a voice from an audio sample (10–30s of clean speech works well).
-  //    `consent` is REQUIRED: a JSON string attesting you have the speaker's
-  //    permission to clone their voice. Use the real consenting person's details.
+  // 1. Get (or reuse) a consent challenge. Its `phrase` is what the speaker
+  //    must read aloud; `id` ties the recording to this consent on the create.
+  let challenge = loadChallenge();
+  if (!challenge) {
+    challenge = await client.voices.consentChallenges.create({ full_name: CONSENT_FULL_NAME });
+    fs.writeFileSync(challengeCache, JSON.stringify(challenge, null, 2));
+  }
+
+  // 2. Make sure we have both recordings before spending the (single-use) challenge.
+  const missing = [
+    fs.existsSync(samplePath) ? null : `  sample:  ${samplePath}  (${CONSENT_FULL_NAME}'s voice, 10–30s of clean speech)`,
+    fs.existsSync(consentPath) ? null : `  consent: ${consentPath}  (the SAME person reading the phrase below)`,
+  ].filter(Boolean);
+  if (missing.length > 0) {
+    console.log(
+      `\nConsent required. Have ${CONSENT_FULL_NAME} record themselves reading this phrase, exactly as written:\n\n` +
+        `  "${challenge.phrase}"\n\n` +
+        `Then provide these files and re-run (paths override via SAMPLE_PATH / CONSENT_RECORDING_PATH):\n` +
+        missing.join("\n") +
+        `\n\nChallenge expires ${challenge.expires_at}.\n`,
+    );
+    process.exit(1);
+  }
+
+  // 3. Clone the voice: the sample + the consent recording + the challenge id.
   let voice;
   try {
     voice = await client.voices.create({
       name: "cookbook-cloned-voice",
       gender: "male",
       sample: fs.createReadStream(samplePath),
-      consent: JSON.stringify({ fullName: "Jane Doe", email: "jane@example.com" }),
+      consent_challenge_id: challenge.id,
+      consent_recording: fs.createReadStream(consentPath),
     });
   } catch (err) {
     // Voice cloning is gated by plan. A 402 means it isn't included in yours.
@@ -35,10 +82,11 @@ async function main() {
     }
     throw err;
   }
+  fs.rmSync(challengeCache, { force: true }); // challenge is spent
   console.log(`Cloned voice created: ${voice.id} (${voice.display_name}, type=${voice.type})`);
 
   try {
-    // 2. Synthesize speech using the cloned voice — pass its id as voice_id.
+    // 4. Synthesize speech using the cloned voice — pass its id as voice_id.
     const speech = await client.audio.speech({
       input: "Hello from a voice cloned with the Speechify API.",
       voice_id: voice.id,
@@ -48,7 +96,7 @@ async function main() {
     fs.writeFileSync("output.mp3", Buffer.from(speech.audio_data, "base64"));
     console.log("Wrote output.mp3");
   } finally {
-    // 3. Clean up so cloned voices don't accumulate on your account.
+    // 5. Clean up so cloned voices don't accumulate on your account.
     //    Remove this to keep the voice and reuse it later via voice.id.
     await client.voices.delete({ voice_id: voice.id });
     console.log(`Deleted cloned voice ${voice.id}`);
diff --git a/templates/python/recipe/pyproject.toml b/templates/python/recipe/pyproject.toml
index aa430c4..cdba0c6 100644
--- a/templates/python/recipe/pyproject.toml
+++ b/templates/python/recipe/pyproject.toml
@@ -3,6 +3,6 @@ name = "change-me-python-recipe"
 version = "0.1.0"
 requires-python = ">=3.10"
 dependencies = [
-    "speechify-api>=3.0.1",
+    "speechify-api>=4.0.0",
     "python-dotenv>=1.0.0",
 ]