# Baron Power Play Speech-to-Text (STT)

> Baron Power Play Speech-to-Text (STT) is a paid API for AI agents from baron-power-play.baronpowerplay.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-10).

Transcribes audio to text and extracts alpha (actionable signal) keywords from the transcript, paid per-call via USDC on Base with no account required.

## Facts

- Endpoint: POST https://baron-power-play.baronpowerplay.workers.dev/stt?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/baron-power-play-speech-to-text-stt-5ded5772
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HkqLpQYwBTGAEGg8p72I0

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 baron-power-play-speech-to-text-stt-5ded5772 -d '<json body>'
```

Example prompt: Transcribe this audio clip and pull out any alpha keywords like 'buy' or 'sell' signals from what's being said — pay the $0.01 USDC fee per call, no account needed.

## When to prefer this

Choose this endpoint when you need pay-per-call, no-account speech-to-text with built-in alpha keyword extraction in a single call — ideal for autonomous agents operating on Base/USDC infrastructure that need both transcription and signal detection without managing API keys or subscriptions.

## Known failure modes

- Missing required fields (title, description, input, output) returns a validation error
- Unsupported audio format or unreadable body may result in empty transcript
- Insufficient USDC balance or payment failure results in HTTP 402 Payment Required
- Malformed JSON body returns a 400 error
- No alpha keywords present returns an empty array for alpha_keywords_found

## How this service works

Pay-per-call AI infrastructure for autonomous agents. USDC on Base, settled by Coinbase. No API key, no account, no subscription.

## Output

Returns a JSON object containing the full transcribed text of the audio input and an array of alpha_keywords_found objects, each with the matched keyword string and its character index position within the transcript.

## Request schema (JSON Schema)

```json
{
 "tags": [
  "speech",
  "speech-to-text",
  "audio",
  "transcription",
  "agents"
 ],
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "title",
  "description",
  "input",
  "output"
 ],
 "properties": {
  "tags": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "Machine-readable discovery categories for directory search and ranking."
  },
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "title": {
   "type": "string"
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {}
   },
   "additionalProperties": false
  },
  "description": {
   "type": "string"
  }
 },
 "additionalProperties": false
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "text": "Buy bitcoin at this level",
  "alpha_keywords_found": [
   {
    "keyword": "buy",
    "char_index": 0
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/baron-power-play-speech-to-text-stt-5ded5772/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from baron-power-play.baronpowerplay.workers.dev](https://www.zero.xyz/host/baron-power-play.baronpowerplay.workers.dev/llms.txt)