$ man voice
/voice
PRICE / CALL
$0.05
USDC · base mainnet · scheme: exact
METHOD
POST
CLUSTER
synthforgeCATEGORY
ai
STATUS
● live
NAME
voice — create a hosted audio url for a recurring narration, ivr prompt, or accessibility read-aloud
SYNOPSIS
POST https://x402.agentutility.ai/voice
Content-Type: application/json
X-PAYMENT: <signed-transferWithAuthorization>
{ ... }↳ first call →
402 Payment Required. Sign USDCtransferWithAuthorization, retry with theX-PAYMENT header.DESCRIPTION
Create a hosted audio URL for a recurring narration, IVR prompt, or accessibility read-aloud. Send up to 4,000 characters with a voice, model, speed, and mp3, wav, opus, aac, or flac format; receive audio_url, file size, content type, and the settings used. Save the selected voice settings with the script so the next revision keeps the same narrator. The finished file is hosted on fal.ai storage. Use it as a text-to-speech API, repeatable narration API, script-to-audio service, or accessibility read-aloud.
INPUT — request schema
| property | type | description | req? |
|---|---|---|---|
| text | string | Text to synthesize into speech. Max 4000 chars. | required |
| voice | string | Voice id, e.g. 'af_sky'. Optional, default 'af_sky'. | optional |
| model | string | TTS model id. Optional, default 'tts-kokoro'. | optional |
| speed | number | Playback speed multiplier. Optional, 0.25-4, default 1. | optional |
| format | string | Output audio format: mp3, wav, opus, aac, or flac. Optional, default mp3. enum: mp3 · wav · opus · aac · flac | optional |
OUTPUT — response shape
| field | type | description |
|---|---|---|
| audio_url | string | Signed URL to the generated audio file hosted on R2 or similar object storage. |
| file_size_bytes | number | Size of the generated audio file in bytes. |
| content_type | string | MIME type of the audio response, like audio/mpeg or audio/wav. |
| format | string | Audio container/codec returned: mp3, wav, opus, aac, or flac. |
| voice | string | Voice ID used for synthesis, like af_sky. |
| model | string | TTS model that produced the audio: Kokoro, xAI, ElevenLabs, Orpheus, or MiniMax. |
| speed | number | Playback speed multiplier applied during synthesis, where 1.0 is normal pace. |
| input_chars | number | Number of characters in the input text that were synthesized. |
EXAMPLES — two ways to call
EXAMPLE 1 · curl
curl -X POST https://x402.agentutility.ai/voice \
-H 'Content-Type: application/json' \
-d '{ }'first response =
402 Payment Required with payment requirements; sign + retry with X-PAYMENT.EXAMPLE 2 · mcp
# Install the MCP package for this endpoint's cluster npx -y @agentutility/mcp-<cluster> # Required: EVM private key with USDC on Base export X402_PRIVATE_KEY=0x... # Then call the voice tool from your MCP-aware agent.
MCP server handles payment automatically — your coding agent just calls the tool by name.
METADATA
- tags
- ttsspeechaudiovoiceai
- env
- VENICE_API_KEY · FAL_KEY
- methods
- POST
- cluster
- synthforge
- price
- $0.05 USDC per call
ADJACENT — other endpoints in synthforge
| endpoint | description | price |
|---|---|---|
| text-to-speech | Generate a hosted audio URL each time an updated script needs the same narrator. | $0.05 |
| image-generate-pro | Premium text-to-image API for repeatable product, campaign, and design assets when a standard draft needs a selected model tier. | $0.06 |
| recraft | Generates SFW design and illustration images with Venice's recraft-v4 model on a dedicated endpoint. | $0.06 |
| seedream | Generates SFW images with Venice's seedream-v4 model on a dedicated endpoint. | $0.06 |
| flux-2-pro | Generates SFW images with Venice's flux-2-pro model on a dedicated endpoint. | $0.04 |
| qwen-image | Generates SFW images with Venice's qwen-image model on a dedicated endpoint. | $0.04 |
| background-remove | Removes the background from a public image URL and returns the subject with alpha transparency. | $0.08 |
| background-remover | Removes the background from product, portrait, and object images, returning alpha PNG foreground cutouts with optional crop-to-bounding-b… | $0.08 |
SEE ALSO