diff --git a/ai_agents/agents/integration_tests/tts_guarder/tests/bin/start b/ai_agents/agents/integration_tests/tts_guarder/tests/bin/start
index 4afef8466f..83642cc985 100755
--- a/ai_agents/agents/integration_tests/tts_guarder/tests/bin/start
+++ b/ai_agents/agents/integration_tests/tts_guarder/tests/bin/start
@@ -9,7 +9,7 @@ EXTENSION_NAME=${EXT_NAME:-elevenlabs_tts_python}
 
 export PYTHONPATH=.:ten_packages/system/ten_runtime_python/lib:ten_packages/system/ten_runtime_python/interface:ten_packages/system/ten_ai_base/interface:ten_packages/extension/${EXTENSION_NAME}:$PYTHONPATH
 # some tts extension does not support sample rate comparison, so we need to set the enable_sample_rate parameter
-if [[ "${EXTENSION_NAME}" == "humeai_tts_python" || "${EXTENSION_NAME}" == "openai_tts_python" || "${EXTENSION_NAME}" == "openai_tts2_python" || "${EXTENSION_NAME}" == "mistral_tts_python" || "${EXTENSION_NAME}" == "ezai_tw_tts_python" ]]; then
+if [[ "${EXTENSION_NAME}" == "humeai_tts_python" || "${EXTENSION_NAME}" == "openai_tts_python" || "${EXTENSION_NAME}" == "openai_tts2_python" || "${EXTENSION_NAME}" == "mistral_tts_python" || "${EXTENSION_NAME}" == "ezai_tw_tts_python" || "${EXTENSION_NAME}" == "typecast_tts_python" ]]; then
     export ENABLE_SAMPLE_RATE="False"
 else
     export ENABLE_SAMPLE_RATE="True"
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/README.md b/ai_agents/agents/ten_packages/extension/typecast_tts_python/README.md
new file mode 100644
index 0000000000..ff512e4e31
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/README.md
@@ -0,0 +1,35 @@
+# Typecast TTS Extension
+
+Typecast text-to-speech extension for TEN Framework.
+
+The extension uses the official `typecast-python` SDK and Typecast's
+`/v1/text-to-speech/stream` endpoint. Typecast streams WAV audio at 32 kHz,
+16-bit, mono. The extension strips the initial WAV header and forwards PCM16
+mono audio to TEN.
+
+## Configuration
+
+```json
+{
+  "params": {
+    "api_key": "<typecast-api-key>",
+    "url": "https://api.typecast.ai",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30",
+    "output": {
+      "audio_format": "wav"
+    }
+  },
+  "chunk_size": 8192
+}
+```
+
+`output.audio_format` is forced to `wav` because TEN consumes PCM audio frames.
+MP3 streaming would require an additional decoder and is intentionally not used.
+
+## Validation
+
+```bash
+tman -y install --standalone
+./tests/bin/start
+```
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/__init__.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/__init__.py
new file mode 100644
index 0000000000..72593ab225
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/__init__.py
@@ -0,0 +1,6 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+from . import addon
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/addon.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/addon.py
new file mode 100644
index 0000000000..85d8d5980e
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/addon.py
@@ -0,0 +1,15 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+from ten_runtime import Addon, TenEnv, register_addon_as_extension
+
+from .extension import TypecastTTSExtension
+
+
+@register_addon_as_extension("typecast_tts_python")
+class TypecastTTSExtensionAddon(Addon):
+    def on_create_instance(self, ten_env: TenEnv, name: str, context) -> None:
+        ten_env.log_info("TypecastTTSExtensionAddon on_create_instance")
+        ten_env.on_create_instance_done(TypecastTTSExtension(name), context)
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/config.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/config.py
new file mode 100644
index 0000000000..259aa496ac
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/config.py
@@ -0,0 +1,71 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+from pathlib import Path
+from typing import Any
+import copy
+
+from pydantic import Field
+from ten_ai_base import utils
+from ten_ai_base.tts2_http import AsyncTTS2HttpConfig
+
+
+class TypecastTTSConfig(AsyncTTS2HttpConfig):
+    """Typecast TTS config."""
+
+    dump: bool = Field(default=False, description="Typecast TTS dump")
+    dump_path: str = Field(
+        default_factory=lambda: str(
+            Path(__file__).parent / "typecast_tts_in.pcm"
+        ),
+        description="Typecast TTS dump path",
+    )
+    url: str = Field(
+        default="https://api.typecast.ai",
+        description="Typecast API URL",
+    )
+    params: dict[str, Any] = Field(
+        default_factory=dict,
+        description="Typecast TTS params",
+    )
+    chunk_size: int = Field(
+        default=8192,
+        ge=1,
+        description="Maximum bytes read from each Typecast streaming chunk",
+    )
+
+    def update_params(self) -> None:
+        if "url" in self.params:
+            self.url = str(
+                self.params.pop("url")  # pylint: disable=no-member
+            ).rstrip("/")
+        else:
+            self.url = self.url.rstrip("/")
+
+        if "model" not in self.params:
+            self.params["model"] = "ssfm-v30"
+
+        output = dict(
+            self.params.get("output") or {}  # pylint: disable=no-member
+        )
+        output["audio_format"] = "wav"
+        self.params["output"] = output
+
+    def validate(self) -> None:
+        if not self.params.get("api_key"):  # pylint: disable=no-member
+            raise ValueError("api_key is required for Typecast TTS")
+        if not self.params.get("voice_id"):  # pylint: disable=no-member
+            raise ValueError("voice_id is required for Typecast TTS")
+        if not self.params.get("model"):  # pylint: disable=no-member
+            raise ValueError("model is required for Typecast TTS")
+
+    def to_str(self, sensitive_handling: bool = True) -> str:
+        if not sensitive_handling:
+            return f"{self}"
+
+        config = copy.deepcopy(self)
+        if config.params and "api_key" in config.params:
+            config.params["api_key"] = utils.encrypt(config.params["api_key"])
+        return f"{config}"
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/extension.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/extension.py
new file mode 100644
index 0000000000..f052eb4bf8
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/extension.py
@@ -0,0 +1,56 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+from ten_ai_base.tts2_http import (
+    AsyncTTS2HttpClient,
+    AsyncTTS2HttpConfig,
+    AsyncTTS2HttpExtension,
+)
+from ten_ai_base.message import TTSAudioEndReason
+from ten_runtime import AsyncTenEnv
+
+from .config import TypecastTTSConfig
+from .typecast_tts import TYPECAST_STREAM_SAMPLE_RATE, TypecastTTSClient
+
+
+class TypecastTTSExtension(AsyncTTS2HttpExtension):
+    """Typecast TTS extension using Typecast streaming TTS."""
+
+    def __init__(self, name: str) -> None:
+        super().__init__(name)
+        self.config: TypecastTTSConfig = None
+        self.client: TypecastTTSClient = None
+
+    async def create_config(self, config_json_str: str) -> AsyncTTS2HttpConfig:
+        return TypecastTTSConfig.model_validate_json(config_json_str)
+
+    async def create_client(
+        self, config: AsyncTTS2HttpConfig, ten_env: AsyncTenEnv
+    ) -> AsyncTTS2HttpClient:
+        return TypecastTTSClient(config=config, ten_env=ten_env)
+
+    def vendor(self) -> str:
+        return "typecast"
+
+    def synthesize_audio_sample_rate(self) -> int:
+        return TYPECAST_STREAM_SAMPLE_RATE
+
+    async def _send_audio_end_and_finish(
+        self,
+        request_id: str,
+        reason: TTSAudioEndReason,
+        log_message: str | None = None,
+    ) -> None:
+        # The base PCMWriter may retain tail bytes while a write is in flight.
+        # Its cleanup flush then writes those bytes on this second pass.
+        recorder = self.recorder_map.get(request_id)
+        if recorder:
+            await recorder.flush()
+
+        await super()._send_audio_end_and_finish(
+            request_id=request_id,
+            reason=reason,
+            log_message=log_message,
+        )
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/manifest.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/manifest.json
new file mode 100644
index 0000000000..5362033ff2
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/manifest.json
@@ -0,0 +1,83 @@
+{
+  "type": "extension",
+  "name": "typecast_tts_python",
+  "version": "0.1.0",
+  "dependencies": [
+    {
+      "type": "system",
+      "name": "ten_runtime_python",
+      "version": "0.11"
+    },
+    {
+      "type": "system",
+      "name": "ten_ai_base",
+      "version": "0.7"
+    }
+  ],
+  "package": {
+    "include": [
+      "manifest.json",
+      "property.json",
+      "BUILD.gn",
+      "**.tent",
+      "**.py",
+      "README.md",
+      "pyproject.toml",
+      "requirements.txt"
+    ]
+  },
+  "api": {
+    "interface": [
+      {
+        "import_uri": "../../system/ten_ai_base/api/tts-interface.json"
+      }
+    ],
+    "property": {
+      "properties": {
+        "params": {
+          "type": "object",
+          "properties": {
+            "api_key": {
+              "type": "string"
+            },
+            "url": {
+              "type": "string"
+            },
+            "voice_id": {
+              "type": "string"
+            },
+            "model": {
+              "type": "string"
+            },
+            "language": {
+              "type": "string"
+            },
+            "output": {
+              "type": "object",
+              "properties": {
+                "audio_pitch": {
+                  "type": "int64"
+                },
+                "audio_tempo": {
+                  "type": "float64"
+                },
+                "audio_format": {
+                  "type": "string"
+                },
+                "target_lufs": {
+                  "type": "float64"
+                }
+              }
+            },
+            "seed": {
+              "type": "int64"
+            }
+          }
+        },
+        "chunk_size": {
+          "type": "int64"
+        }
+      }
+    }
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/pcm.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/pcm.py
new file mode 100644
index 0000000000..13f674c6cb
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/pcm.py
@@ -0,0 +1,41 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+BYTES_PER_SAMPLE = 2
+NUMBER_OF_CHANNELS = 1
+WAV_HEADER_BYTES = 44
+
+
+class StreamingWavToPcm16:
+    """Strip the first WAV header and return PCM16-aligned chunks."""
+
+    def __init__(self) -> None:
+        self._header = bytearray()
+        self._remainder = bytearray()
+        self._header_stripped = False
+
+    def feed(self, chunk: bytes) -> bytes:
+        if not chunk:
+            return b""
+
+        if not self._header_stripped:
+            needed = WAV_HEADER_BYTES - len(self._header)
+            self._header.extend(chunk[:needed])
+            chunk = chunk[needed:]
+            if len(self._header) < WAV_HEADER_BYTES:
+                return b""
+            self._header_stripped = True
+
+        if self._remainder:
+            chunk = bytes(self._remainder) + chunk
+            self._remainder.clear()
+
+        frame_size = BYTES_PER_SAMPLE * NUMBER_OF_CHANNELS
+        left_size = len(chunk) % frame_size
+        if left_size:
+            self._remainder.extend(chunk[-left_size:])
+            chunk = chunk[:-left_size]
+
+        return bytes(chunk)
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/property.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/property.json
new file mode 100644
index 0000000000..818a04b078
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/property.json
@@ -0,0 +1,13 @@
+{
+  "params": {
+    "api_key": "",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30",
+    "output": {
+      "audio_format": "wav"
+    }
+  },
+  "chunk_size": 8192,
+  "dump": false,
+  "dump_path": "/tmp/typecast_tts_audio_dump"
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/pyproject.toml b/ai_agents/agents/ten_packages/extension/typecast_tts_python/pyproject.toml
new file mode 100644
index 0000000000..929922693c
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/pyproject.toml
@@ -0,0 +1,7 @@
+[project]
+name = "typecast-tts-python"
+version = "0.1.0"
+requires-python = ">=3.10"
+dependencies = [
+    "typecast-python==0.3.9",
+]
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/requirements.txt b/ai_agents/agents/ten_packages/extension/typecast_tts_python/requirements.txt
new file mode 100644
index 0000000000..8bfdac59ff
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/requirements.txt
@@ -0,0 +1 @@
+typecast-python==0.3.9
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/bin/start b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/bin/start
new file mode 100755
index 0000000000..8e78210572
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/bin/start
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+set -e
+
+cd "$(dirname "${BASH_SOURCE[0]}")/../.."
+
+export PYTHONPATH=.ten/app:.ten/app/ten_packages/system/ten_runtime_python/lib:.ten/app/ten_packages/system/ten_runtime_python/interface:.ten/app/ten_packages/system/ten_ai_base/interface:$PYTHONPATH
+
+pytest -s tests/ "$@"
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting1.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting1.json
new file mode 100644
index 0000000000..b71144d433
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting1.json
@@ -0,0 +1,9 @@
+{
+  "dump": false,
+  "dump_path": "./tests/keep_dump_output/",
+  "params": {
+    "api_key": "${env:TYPECAST_API_KEY}",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30"
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting2.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting2.json
new file mode 100644
index 0000000000..b71144d433
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_basic_audio_setting2.json
@@ -0,0 +1,9 @@
+{
+  "dump": false,
+  "dump_path": "./tests/keep_dump_output/",
+  "params": {
+    "api_key": "${env:TYPECAST_API_KEY}",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30"
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_dump.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_dump.json
new file mode 100644
index 0000000000..dfda288a3a
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_dump.json
@@ -0,0 +1,9 @@
+{
+  "dump": true,
+  "dump_path": "./dump/",
+  "params": {
+    "api_key": "${env:TYPECAST_API_KEY}",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30"
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_invalid.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_invalid.json
new file mode 100644
index 0000000000..2dfc3ec4b9
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_invalid.json
@@ -0,0 +1,7 @@
+{
+  "params": {
+    "api_key": "invalid",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30"
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_miss_required.json b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_miss_required.json
new file mode 100644
index 0000000000..f2d17f03de
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/configs/property_miss_required.json
@@ -0,0 +1,7 @@
+{
+  "params": {
+    "api_key": "",
+    "voice_id": "tc_60e5426de8b95f1d3000d7b5",
+    "model": "ssfm-v30"
+  }
+}
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/test_typecast_tts.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/test_typecast_tts.py
new file mode 100644
index 0000000000..e467971342
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/tests/test_typecast_tts.py
@@ -0,0 +1,267 @@
+import sys
+from pathlib import Path
+import asyncio
+import json
+import threading
+from unittest.mock import AsyncMock, MagicMock, patch
+
+import pytest
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[1]))
+sys.path.insert(0, str(Path(__file__).resolve().parents[2]))
+
+from ten_runtime import AsyncExtensionTester, AsyncTenEnvTester, Data, TenError
+from ten_runtime import TenErrorCode
+from ten_ai_base.struct import TTS2HttpResponseEventType, TTSTextInput
+from ten_ai_base.helper import PCMWriter
+from ten_ai_base.helper import write_pcm_to_file
+from ten_ai_base.message import TTSAudioEndReason
+from ten_ai_base.tts2_http import AsyncTTS2HttpExtension
+
+from pcm import StreamingWavToPcm16
+from typecast_tts_python.config import TypecastTTSConfig
+from typecast_tts_python.extension import TypecastTTSExtension
+from typecast_tts_python.typecast_tts import TypecastTTSClient
+from typecast import TypecastError, UnauthorizedError
+
+
+def test_config_defaults_and_forces_wav():
+    config = TypecastTTSConfig(
+        params={
+            "api_key": "key",
+            "voice_id": "voice",
+            "url": "https://example.com/",
+            "output": {"audio_format": "mp3", "audio_tempo": 1.1},
+        }
+    )
+
+    config.update_params()
+    config.validate()
+
+    assert config.url == "https://example.com"
+    assert "url" not in config.params
+    assert config.params["model"] == "ssfm-v30"
+    assert config.params["output"] == {
+        "audio_format": "wav",
+        "audio_tempo": 1.1,
+    }
+
+
+@pytest.mark.parametrize("missing", ["api_key", "voice_id"])
+def test_config_requires_credentials_and_voice(missing):
+    params = {"api_key": "key", "voice_id": "voice"}
+    params[missing] = ""
+    config = TypecastTTSConfig(params=params)
+    config.update_params()
+
+    with pytest.raises(ValueError, match=missing):
+        config.validate()
+
+
+def test_streaming_wav_to_pcm16_strips_header_across_chunks():
+    converter = StreamingWavToPcm16()
+    header = b"h" * 44
+
+    assert converter.feed(header[:20]) == b""
+    assert converter.feed(header[20:] + b"\x01\x02\x03") == b"\x01\x02"
+    assert converter.feed(b"\x04\x05") == b"\x03\x04"
+    assert converter.feed(b"\x06") == b"\x05\x06"
+
+
+def test_streaming_wav_to_pcm16_strips_header_in_single_chunk():
+    converter = StreamingWavToPcm16()
+    header = b"h" * 44
+
+    assert converter.feed(header + b"\x01\x02\x03\x04") == b"\x01\x02\x03\x04"
+
+
+def test_extension_flushes_dump_tail_added_during_write(tmp_path):
+    output = tmp_path / "dump.pcm"
+    first_write_started = threading.Event()
+    release_first_write = threading.Event()
+    write_count = 0
+
+    def delayed_write(buffer, file_name):
+        nonlocal write_count
+        write_count += 1
+        if write_count == 1:
+            first_write_started.set()
+            release_first_write.wait()
+        write_pcm_to_file(buffer, file_name)
+
+    async def run():
+        writer = PCMWriter(str(output), buffer_size=4)
+        extension = TypecastTTSExtension("test")
+        extension.recorder_map = {"request-id": writer}
+
+        async def base_finish(self, request_id, reason, log_message=None):
+            await self.recorder_map[request_id].flush()
+
+        with patch(
+            "ten_ai_base.helper.write_pcm_to_file",
+            side_effect=delayed_write,
+        ), patch.object(
+            AsyncTTS2HttpExtension,
+            "_send_audio_end_and_finish",
+            base_finish,
+        ):
+            await writer.write(b"head")
+            while not first_write_started.is_set():
+                await asyncio.sleep(0)
+            await writer.write(b"tail")
+            flush_task = asyncio.create_task(
+                extension._send_audio_end_and_finish(
+                    request_id="request-id",
+                    reason=TTSAudioEndReason.REQUEST_END,
+                )
+            )
+            await asyncio.sleep(0)
+            release_first_write.set()
+            await flush_task
+
+    asyncio.run(run())
+
+    assert output.read_bytes() == b"headtail"
+
+
+def test_client_empty_text_ends_without_request():
+    config = TypecastTTSConfig(params={"api_key": "key", "voice_id": "voice"})
+    config.update_params()
+    client = TypecastTTSClient(config, MagicMock())
+
+    async def collect():
+        return [event async for event in client.get("  ", "request-id")]
+
+    assert asyncio.run(collect()) == [(None, TTS2HttpResponseEventType.END)]
+
+
+@pytest.mark.parametrize(
+    ("error", "expected_event"),
+    [
+        (
+            UnauthorizedError("invalid key"),
+            TTS2HttpResponseEventType.INVALID_KEY_ERROR,
+        ),
+        (TypecastError("rate limited", 429), TTS2HttpResponseEventType.ERROR),
+    ],
+)
+def test_client_maps_vendor_errors(error, expected_event):
+    config = TypecastTTSConfig(params={"api_key": "key", "voice_id": "voice"})
+    config.update_params()
+    client = TypecastTTSClient(config, MagicMock())
+
+    async def failing_stream(request, chunk_size):
+        raise error
+        yield b""  # pragma: no cover
+
+    mock_sdk = MagicMock()
+    mock_sdk.__aenter__ = AsyncMock(return_value=mock_sdk)
+    mock_sdk.__aexit__ = AsyncMock(return_value=None)
+    mock_sdk.text_to_speech_stream = failing_stream
+
+    async def collect():
+        with patch(
+            "typecast_tts_python.typecast_tts.AsyncTypecast",
+            return_value=mock_sdk,
+        ):
+            return [event async for event in client.get("hello", "request-id")]
+
+    events = asyncio.run(collect())
+    assert events == [(str(error).encode(), expected_event)]
+
+
+class TypecastTTSExtensionTester(AsyncExtensionTester):
+    def __init__(self):
+        super().__init__()
+        self.audio_end_received = False
+        self.received_audio_chunks = []
+
+    async def on_start(self, ten_env: AsyncTenEnvTester) -> None:
+        tts_input = TTSTextInput(
+            request_id="tts_request_1",
+            text="hello typecast",
+            text_input_end=True,
+        )
+        data = Data.create("tts_text_input")
+        data.set_property_from_json(None, tts_input.model_dump_json())
+        await ten_env.send_data(data)
+        asyncio.create_task(self._stop_on_timeout(ten_env))
+
+    async def on_data(self, ten_env: AsyncTenEnvTester, data: Data) -> None:
+        if data.get_name() == "tts_audio_end":
+            data_json, _ = data.get_property_to_json()
+            data_dict = json.loads(data_json)
+            assert data_dict["request_id"] == "tts_request_1"
+            self.audio_end_received = True
+            ten_env.stop_test()
+
+    async def on_audio_frame(self, ten_env: AsyncTenEnvTester, audio_frame):
+        buf = audio_frame.lock_buf()
+        try:
+            self.received_audio_chunks.append(bytes(buf))
+        finally:
+            audio_frame.unlock_buf(buf)
+
+    async def _stop_on_timeout(self, ten_env: AsyncTenEnvTester) -> None:
+        await asyncio.sleep(10)
+        ten_env.stop_test(
+            TenError.create(
+                error_code=TenErrorCode.ErrorCodeGeneric,
+                error_message="test timeout",
+            )
+        )
+
+
+def test_typecast_tts_extension_success():
+    wav_header = b"h" * 44
+    audio_chunk_1 = b"\x01\x02\x03\x04"
+    audio_chunk_2 = b"\x05\x06\x07\x08"
+
+    async def mock_text_to_speech_stream(request, chunk_size):
+        assert request.text == "hello typecast"
+        assert request.output.audio_format == "wav"
+        assert chunk_size == 8192
+        yield wav_header[:20]
+        yield wav_header[20:] + audio_chunk_1
+        yield audio_chunk_2
+
+    with patch("typecast_tts_python.typecast_tts.AsyncTypecast") as mock_cls:
+        mock_client = MagicMock()
+        mock_client.__aenter__ = AsyncMock(return_value=mock_client)
+        mock_client.__aexit__ = AsyncMock(return_value=None)
+        mock_client.text_to_speech_stream = mock_text_to_speech_stream
+        mock_cls.return_value = mock_client
+
+        property_json = {
+            "params": {
+                "api_key": "test_api_key",
+                "voice_id": "test_voice_id",
+                "model": "ssfm-v30",
+            }
+        }
+
+        tester = TypecastTTSExtensionTester()
+        tester.set_test_mode_single(
+            "typecast_tts_python", json.dumps(property_json)
+        )
+
+        err = tester.run()
+
+    assert err is None, (
+        "test_typecast_tts_extension_success err: "
+        f"{err.error_message() if err else 'None'}"
+    )
+    assert tester.audio_end_received
+    assert b"".join(tester.received_audio_chunks) == (
+        audio_chunk_1 + audio_chunk_2
+    )
+    mock_cls.assert_called_once_with(
+        host="https://api.typecast.ai",
+        api_key="test_api_key",
+    )
+    mock_client.__aexit__.assert_awaited_once_with(None, None, None)
+
+
+if __name__ == "__main__":
+    test_streaming_wav_to_pcm16_strips_header_across_chunks()
+    test_streaming_wav_to_pcm16_strips_header_in_single_chunk()
diff --git a/ai_agents/agents/ten_packages/extension/typecast_tts_python/typecast_tts.py b/ai_agents/agents/ten_packages/extension/typecast_tts_python/typecast_tts.py
new file mode 100644
index 0000000000..a4383b4095
--- /dev/null
+++ b/ai_agents/agents/ten_packages/extension/typecast_tts_python/typecast_tts.py
@@ -0,0 +1,121 @@
+#
+# This file is part of TEN Framework, an open source project.
+# Licensed under the Apache License, Version 2.0.
+# See the LICENSE file for more information.
+#
+from typing import Any, AsyncIterator, Tuple
+
+from ten_ai_base.const import LOG_CATEGORY_VENDOR
+from ten_ai_base.struct import TTS2HttpResponseEventType
+from ten_ai_base.tts2_http import AsyncTTS2HttpClient
+from ten_runtime import AsyncTenEnv
+from typecast import AsyncTypecast, TypecastError
+from typecast.models import TTSRequestStream
+
+from .config import TypecastTTSConfig
+from .pcm import StreamingWavToPcm16
+
+TYPECAST_STREAM_SAMPLE_RATE = 32000
+
+
+class TypecastTTSClient(AsyncTTS2HttpClient):
+    """Typecast TTS client backed by the official Typecast Python SDK."""
+
+    def __init__(self, config: TypecastTTSConfig, ten_env: AsyncTenEnv):
+        super().__init__()
+        self.config = config
+        self.ten_env = ten_env
+        self._is_cancelled = False
+        self._client: AsyncTypecast | None = None
+
+        ten_env.log_info(f"TypecastTTS initialized with URL: {self.config.url}")
+
+    async def _ensure_client(self) -> AsyncTypecast:
+        if self._client is None:
+            self._client = AsyncTypecast(
+                host=self.config.url,
+                api_key=self.config.params["api_key"],
+            )
+            await self._client.__aenter__()
+        return self._client
+
+    async def cancel(self):
+        self.ten_env.log_debug("TypecastTTS: cancel() called.")
+        self._is_cancelled = True
+
+    async def get(
+        self, text: str, request_id: str
+    ) -> AsyncIterator[Tuple[bytes | None, TTS2HttpResponseEventType]]:
+        self._is_cancelled = False
+
+        if len(text.strip()) == 0:
+            self.ten_env.log_warn(
+                f"TypecastTTS: empty text for request_id: {request_id}.",
+                category=LOG_CATEGORY_VENDOR,
+            )
+            yield None, TTS2HttpResponseEventType.END
+            return
+
+        try:
+            payload = {**self.config.params}
+            payload.pop("api_key", None)
+
+            output = dict(payload.get("output") or {})
+            output["audio_format"] = "wav"
+            payload["output"] = output
+            payload["text"] = text
+
+            request = TTSRequestStream.model_validate(payload)
+            converter = StreamingWavToPcm16()
+            client = await self._ensure_client()
+
+            self.ten_env.log_debug(
+                f"TypecastTTS: sending request for request_id: {request_id}"
+            )
+
+            async for chunk in client.text_to_speech_stream(
+                request, chunk_size=self.config.chunk_size
+            ):
+                if self._is_cancelled:
+                    self.ten_env.log_debug(
+                        f"Cancellation detected, flushing TTS stream for request_id: {request_id}"
+                    )
+                    yield None, TTS2HttpResponseEventType.FLUSH
+                    return
+
+                pcm = converter.feed(chunk)
+                if pcm:
+                    yield pcm, TTS2HttpResponseEventType.RESPONSE
+
+            if not self._is_cancelled:
+                self.ten_env.log_debug(
+                    f"TypecastTTS: sending END event for request_id: {request_id}"
+                )
+                yield None, TTS2HttpResponseEventType.END
+
+        except Exception as e:
+            error_message = str(e)
+            self.ten_env.log_error(
+                f"vendor_error: {error_message} for request_id: {request_id}",
+                category=LOG_CATEGORY_VENDOR,
+            )
+            event = (
+                TTS2HttpResponseEventType.INVALID_KEY_ERROR
+                if isinstance(e, TypecastError)
+                and getattr(e, "status_code", None) in (401, 403)
+                else TTS2HttpResponseEventType.ERROR
+            )
+            yield error_message.encode("utf-8"), event
+
+    async def clean(self):
+        self.ten_env.log_debug("TypecastTTS: clean() called.")
+        if self._client is not None:
+            await self._client.__aexit__(None, None, None)
+            self._client = None
+
+    def get_extra_metadata(self) -> dict[str, Any]:
+        return {
+            "vendor": "typecast",
+            "model": self.config.params.get("model", ""),
+            "voice_id": self.config.params.get("voice_id", ""),
+        }