# x402 Transcription API

> x402 Transcription API is a paid API for AI agents from x402-transcribe-mainnet.hustlescan-media.workers.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-20).

Transcribes short MP3 or WAV audio files using Whisper Large V3 Turbo, returning text, detected language, duration, and timestamped segments, paid per-use with USDC on Base.

## Facts

- Endpoint: GET https://x402-transcribe-mainnet.hustlescan-media.workers.dev/api/transcribe?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-transcription-api-0c431e35
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DfX2jn0Hb28DpDhtMidJd

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 x402-transcription-api-0c431e35
```

Example prompt: Can you transcribe the audio at https://example.com/interview.mp3 and give me the full text along with timestamps for each segment?

## When to prefer this

Choose this endpoint when you need quick, pay-per-use audio-to-text transcription without account setup or API keys, and your audio is a publicly accessible MP3 or uncompressed PCM WAV file under 2 MB and 120 seconds. It is ideal for one-off transcription tasks, agent workflows with variable audio volume, or when you want timestamped segments and language detection in a single call. Prefer alternatives if you need batch processing of large files, support for other audio formats, speaker diarization, or real-time streaming transcription.

## Known failure modes

- Audio file exceeds 2 MB or 120 seconds — request rejected before transcription
- Non-HTTPS or credentialed/IP-based URLs are rejected by schema validation
- Unsupported audio format (e.g. AAC, OGG, compressed WAV) — transcription fails
- URL is unreachable or returns non-audio content — no transcript returned, not charged
- Payment in USDC on Base fails or is insufficient — request blocked at x402 payment layer

## How this service works

Pay-per-use AI audio transcription API. Transcribe short MP3 and WAV audio files using Whisper Large V3 Turbo. No account or API key required. Pay with USDC on Base. 0.02 USDC per request. Maximum 120 seconds and 2 MB; MP3 and uncompressed PCM WAV only. Returns JSON: text, detected language, duration and timestamped segments. Charged only when a transcript is returned.

## Output

A JSON object containing: 'success' (boolean), 'text' (full transcript string), 'language' (ISO 639-1 code of detected language), 'duration_seconds' (length of the audio), and 'segments' (array of objects each with 'start', 'end', and 'text' for timestamped chunks of the transcript). Returned only when transcription succeeds; charged 0.02 USDC per successful response.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "pattern": "^https://",
       "maxLength": 2048,
       "description": "Direct https:// link to an MP3 or uncompressed PCM WAV file: at most 2 MB and 120 seconds. No credentials, IP addresses or custom ports in the URL."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "success",
      "text"
     ],
     "properties": {
      "text": {
       "type": "string"
      },
      "success": {
       "type": "boolean"
      },
      "language": {
       "type": "string",
       "description": "ISO 639-1 code where known"
      },
      "segments": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "start",
         "end",
         "text"
        ],
        "properties": {
         "end": {
          "type": "number"
         },
         "text": {
          "type": "string"
         },
         "start": {
          "type": "number"
         }
        }
       }
      },
      "duration_seconds": {
       "type": "number"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-transcription-api-0c431e35/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-transcribe-mainnet.hustlescan-media.workers.dev](https://www.zero.xyz/host/x402-transcribe-mainnet.hustlescan-media.workers.dev/llms.txt)