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speech-use

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Generate (TTS), Transcribe (STT), and Clone voices using Google's GenAI and Cloud Speech SDKs. Supports Gemini-TTS, Chirp 3, and Instant Custom Voice.

QUICK START

How to use this skill

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  1. Open your project in Codex.
  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/cnemri/google-genai-skills/blob/HEAD/skills/speech-use/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/speech-use/. Do not write files or run scripts until I approve.

After I approve, install the complete skill folder, including required referenced files, into that project location. Verify it is discoverable, then tell me its actual invocation name and how to use it. Do not claim it is installed until you have verified it.

Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Speech Use

Use this skill to perform Text-to-Speech (TTS), Speech-to-Text (STT), and Voice Cloning operations.

This skill uses portable Python scripts managed by uv.

Prerequisites

  1. Environment Variables:

    • GOOGLE_API_KEY (for TTS via Gemini)
    • GOOGLE_CLOUD_PROJECT (Required for STT and Voice Cloning)
    • GOOGLE_APPLICATION_CREDENTIALS (Recommended for STT/Voice Cloning)

  2. APIs Enabled:

    • Text-to-Speech API (texttospeech.googleapis.com)
    • Speech-to-Text API (speech.googleapis.com)

Usage

1. Generate Speech (TTS)

Generate audio from text using Gemini-TTS.

Standard Voice:

uv run skills/speech-use/scripts/generate_speech.py "Hello world, this is a test." --voice Puck --output hello.wav

Custom Voice (Cloned):

uv run skills/speech-use/scripts/generate_speech.py "This is my custom voice speaking." --voice-cloning-key "YOUR_KEY_HERE" --output custom.wav

2. Create Custom Voice (Voice Cloning)

Generate a voiceCloningKey from a reference audio file and a consent file.

Requirements:

  • reference.wav: 10-30s of clear speech (the voice to clone).
  • consent.wav: The speaker saying: "I am the owner of this voice and I consent to Google using this voice to create a synthetic voice model."
uv run skills/speech-use/scripts/create_custom_voice.py --reference-audio reference.wav --consent-audio consent.wav

Save the output key to use with generate_speech.py.

3. Transcribe Audio (STT)

Transcribe audio files using Chirp 3.

uv run skills/speech-use/scripts/transcribe_audio.py audio.wav --language en-US --output transcript.txt

Options

generate_speech.py

  • --voice: Prebuilt voice (e.g., Kore, Puck, Fenrir, Aoede).
  • --voice-cloning-key: Key from create_custom_voice.py.
  • --model: Default gemini-2.5-flash-preview-tts.

transcribe_audio.py

  • --model: Default chirp_3.
  • --language: Default auto.
  • --location: Cloud region (default us).

References

Before running scripts, review the reference guides for available voices and options.

  • Voices Guide - 30+ voice options with styles (Puck, Kore, Fenrir, Aoede, etc.)