# PennyPress River of Time Audio Edition

> PennyPress River of Time Audio Edition is a paid API for AI agents from www.pennypress.org, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-27).

Returns the spoken MP3 audio edition of the essay 'River of Time' from PennyPress, delivered after micropayment.

## Facts

- Endpoint: GET https://www.pennypress.org/essays/river-of-time/audio?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-27
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennypress-river-of-time-audio-edition-9233e049
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tbXrRkUlrKXja1hUe4i7U

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 pennypress-river-of-time-audio-edition-9233e049
```

Example prompt: Can you fetch the spoken MP3 audio of the 'River of Time' essay from PennyPress for me so I can listen to it?

## When to prefer this

Choose this endpoint when a user specifically wants to listen to the 'River of Time' essay in audio/MP3 format from PennyPress, and is willing to pay a $0.10 USDC micropayment via the x402 protocol. Prefer this over text-based essay endpoints when the use case is auditory consumption, accessibility, or offline listening.

## Known failure modes

- Payment not provided or insufficient — endpoint returns 402 Payment Required
- Invalid or missing x402 payment header — authentication/payment failure
- Network timeout if the audio file is large and server is slow
- Endpoint unavailable or returns 5xx if PennyPress server is down
- HEAD or DELETE method used instead of GET may return no audio body

## How this service works

Spoken edition of River of Time as MP3.

## Output

An MP3 audio file containing the spoken narration of the 'River of Time' essay, delivered after the x402 micropayment of $0.10 USDC is processed. The response includes the essay title, format (MP3), content (audio bytes or URL), and associated metadata such as description and publication details.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "title",
      "format",
      "content"
     ],
     "properties": {
      "slug": {
       "type": "string"
      },
      "type": {
       "type": "string"
      },
      "price": {
       "type": "string"
      },
      "title": {
       "type": "string"
      },
      "format": {
       "type": "string"
      },
      "content": {
       "type": "string",
       "description": "Spoken MP3 audio, delivered after payment."
      },
      "description": {
       "type": "string"
      },
      "publication": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennypress-river-of-time-audio-edition-9233e049/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.pennypress.org](https://www.zero.xyz/host/www.pennypress.org/llms.txt)