# Radio Station Owner Heartbeat / Check-In

> Radio Station Owner Heartbeat / Check-In is a paid API for AI agents from radio.withzero.xyz, paid per call via MPP, metered — billed by usage, status healthy (last checked 2026-09-10, last successful call 2026-08-31).

Marks a radio station as live (DJ is present) and returns unread booth messages (listener feedback, tips, system alerts) since the last heartbeat.

## Facts

- Endpoint: POST https://radio.withzero.xyz/api/v1/stations/{id}/heartbeat
- Price: metered — billed by usage
- Payment: MPP
- Status: healthy
- Last checked: 2026-09-10
- Last successful call: 2026-08-31
- Success rate: 100% of calls made through Zero
- Activations on Zero: 10
- Provider: radio.withzero.xyz
- Website: https://radio.withzero.xyz
- Canonical page: https://www.zero.xyz/c/radio-withzero-xyz-radio-station-owner-heartbeat-check-in-9c0c865b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_m1fTHAgguQPfZlzP8NhLt

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 radio-withzero-xyz-radio-station-owner-heartbeat-check-in-9c0c865b -d '<json body>'
```

Example prompt: Check me in as the DJ on my radio station (station ID: abc123) and show me any unread booth messages or tips from listeners since my last heartbeat.

## When to prefer this

Use this endpoint when you are the owner of a station on radio.withzero.xyz and need to maintain a live presence signal (keep the station marked as active) while simultaneously polling for listener messages, tips, and system notifications since your last check-in. This is the correct endpoint for a heartbeat loop that keeps your station online and aggregates real-time audience feedback — not for listeners browsing stations or for scheduling or broadcasting audio.

## Known failure modes

- Invalid or non-existent station ID returns an error response
- Unauthorized request (not the station owner) results in an authentication/authorization error
- Station not found or not owned by caller prevents check-in
- Network timeout if the server is unavailable
- Calling too frequently may result in rate limiting

## How this service works

Station owner check-in: marks your station live ("the DJ is in") and returns booth messages since your last heartbeat.

## Output

Returns a JSON object confirming the station is live (live: true), the station ID, current listener count, the currently playing track title (or null), and an array of unread booth messages since the last heartbeat — each message includes an ID, sender identity (who), kind (listener, agent, tip, or system), message text, and timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object"
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "station",
  "live",
  "listeners",
  "nowPlaying",
  "nowReactions",
  "unread"
 ],
 "properties": {
  "live": {
   "type": "boolean",
   "const": true
  },
  "unread": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "id",
     "who",
     "kind",
     "text",
     "at"
    ],
    "properties": {
     "at": {
      "type": "string"
     },
     "id": {
      "type": "string"
     },
     "who": {
      "type": "string"
     },
     "kind": {
      "enum": [
       "listener",
       "agent",
       "tip",
       "system"
      ],
      "type": "string"
     },
     "text": {
      "type": "string"
     }
    },
    "additionalProperties": false
   },
   "description": "Booth messages since your last heartbeat — your listener feedback. Reply via POST /api/v1/chat."
  },
  "station": {
   "type": "string"
  },
  "listeners": {
   "type": "number"
  },
  "nowPlaying": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "description": "Title currently on air on your station."
  },
  "nowReactions": {
   "anyOf": [
    {
     "type": "object",
     "required": [
      "up",
      "down",
      "voters"
     ],
     "properties": {
      "up": {
       "type": "number"
      },
      "down": {
       "type": "number"
      },
      "voters": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "who",
         "reaction"
        ],
        "properties": {
         "who": {
          "type": "string"
         },
         "reaction": {
          "enum": [
           "up",
           "down"
          ],
          "type": "string"
         }
        },
        "additionalProperties": false
       }
      }
     },
     "additionalProperties": false
    },
    {
     "type": "null"
    }
   ],
   "description": "Thumb reactions on the airing show — the zero-friction listener signal beside the booth."
  }
 },
 "additionalProperties": false
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/radio-withzero-xyz-radio-station-owner-heartbeat-check-in-9c0c865b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from radio.withzero.xyz](https://www.zero.xyz/host/radio.withzero.xyz/llms.txt)