OpenAI Go SDK Realtime Voice Example #

This example sends spoken audio to CLIProxyAPI and saves the model's spoken reply as a WAV file.

It uses the official github.com/openai/openai-go/v3 SDK to create a short-lived Realtime client secret. The official Go SDK currently exposes the Realtime REST resources but does not provide a WebSocket connection helper, so github.com/gorilla/websocket is used for the standard Realtime audio events.

Prerequisites #

1. Start CLIProxyAPI with at least one working ChatGPT/Codex OAuth credential.
2. Configure a proxy API key in config.yaml.
3. Use Go 1.26 or newer.
4. Prepare a PCM WAV file with these exact properties:
   • 24,000 Hz sample rate
   • 16-bit signed PCM
   • mono
   • little-endian

Convert an existing recording with FFmpeg:

ffmpeg -i recording.m4a -ar 24000 -ac 1 -c:a pcm_s16le question.wav

Run #

cd examples/realtime-openai-go

OPENAI_BASE_URL="http://127.0.0.1:8317/v1" \
OPENAI_API_KEY="your-proxy-api-key" \
OPENAI_REALTIME_MODEL="gpt-realtime-2.1" \
OPENAI_REALTIME_INPUT_WAV="question.wav" \
OPENAI_REALTIME_OUTPUT_WAV="response.wav" \
go run .

Expected output:

Loaded question.wav (2.4s, 115200 PCM bytes)
Connected to ws://127.0.0.1:8317/v1/realtime?model=gpt-realtime-2.1 using model gpt-realtime-2.1 and voice marin
Sent 2.4s of speech audio
Assistant transcript: The connection is working correctly.
Saved spoken response to response.wav (1.8s, 86400 PCM bytes)

Play the response:

# macOS
afplay response.wav

# Linux
aplay response.wav

# Cross-platform with FFmpeg
ffplay -autoexit response.wav

Environment variables #

Variable	Required	Default	Description
OPENAI_API_KEY	Yes	—	API key configured for CLIProxyAPI.
OPENAI_REALTIME_INPUT_WAV	Yes	—	Input speech WAV file. It must be 24kHz, 16-bit, mono PCM.
OPENAI_REALTIME_OUTPUT_WAV	No	response.wav	Destination for the spoken response.
OPENAI_BASE_URL	No	http://127.0.0.1:8317/v1	CLIProxyAPI OpenAI-compatible base URL. /v1 is added when the URL has no path.
OPENAI_REALTIME_MODEL	No	gpt-realtime-2.1	Standard Realtime model name. CLIProxyAPI uses it for the upstream standard WebSocket while selecting a compatible Codex OAuth credential internally.
OPENAI_REALTIME_VOICE	No	marin	Realtime output voice. Other common values include cedar, alloy, ash, coral, and echo.
OPENAI_REALTIME_INSTRUCTIONS	No	Short spoken response instruction	Session instructions attached to the client secret.
OPENAI_REALTIME_DEBUG	No	false	Print every received Realtime server event.

Audio flow #

1. The official OpenAI Go SDK calls POST /v1/realtime/client_secrets with an audio session configured for 24kHz PCM input and output.
2. The returned local ek_... credential authenticates the /v1/realtime WebSocket.
3. Input WAV samples are sent in 200ms input_audio_buffer.append chunks.
4. The client sends input_audio_buffer.commit and response.create.
5. Base64 response.output_audio.delta events are decoded and written to the output WAV.

The client secret returned by CLIProxyAPI is local to that proxy instance and is not valid against api.openai.com.

Test #

go test -race ./...

The test starts an in-process HTTP/WebSocket server and verifies client-secret configuration, input audio streaming, output audio decoding, and WAV generation.