# GEDX402 Speech Transcription

> GEDX402 Speech Transcription is a paid API for AI agents from media.gedx402.com, paid per call via x402, $0.0077/call, not verified (last probed 2026-10-11); live alternatives: AgentUtility Video Transcription ($0.1) and medien.halowerk.com Speech-to-Text ($0.02).

Agents call it through Zero, which pays per call: no API key and no wallet of your own. New accounts start with $5.

Live alternatives for the same use case:
- [AgentUtility Video Transcription](https://www.zero.xyz/c/agentutility-video-transcription-whisper-v3-83d051eb) ($0.1)
- [medien.halowerk.com Speech-to-Text](https://www.zero.xyz/c/medien-halowerk-com-speech-to-text-stt-22257e66) ($0.02)

Transcribes audio content (base64-encoded WAV/MP3/etc.) into text using AI, payable per-call with USDC on multiple blockchains

## Facts

- Endpoint: GET https://media.gedx402.com/v1/speech/transcribe?utm_source=zero.xyz
- Price: $0.0077/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Success rate: 0% of calls made through Zero
- Activations on Zero: 3
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gedx402-speech-transcription-bbe9566d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nakZDn-Oxl9-8ru5etI3D

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability gedx402-speech-transcription-bbe9566d
```

Example prompt: Can you transcribe this audio recording for me? Here's the base64-encoded MP3 — just give me back the spoken text.

## When to prefer this

Choose this endpoint when you need pay-per-call audio transcription with no API key setup, especially when you want to pay with USDC on Base, Polygon, Arbitrum, World, or Solana. Ideal for agents that need lightweight, on-demand speech-to-text without managing API credentials or subscriptions.

## Known failure modes

- Invalid or malformed base64 audio input returns an error
- Unsupported audio format may fail or produce garbled output
- Payment failure on supported chain results in 402 response blocking the call
- Very long or large audio files may time out or be rejected
- Empty audio field returns an error or empty transcript

## How this service works

Voice agent bundle — prepaid flux ASR, smart-turn, chat/fast, and TTS loop.

## Output

A JSON object containing a 'text' field with the transcribed speech as a plain-text string, e.g. {"text": "Transcribed speech."}

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "audio": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "text": "Transcribed speech."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gedx402-speech-transcription-bbe9566d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from media.gedx402.com](https://www.zero.xyz/host/media.gedx402.com/llms.txt)