# BitBooth Echo Endpoint (x402)

> BitBooth Echo Endpoint (x402) is a paid API for AI agents from app.heinrichstech.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12, last successful call 2026-07-01).

Accepts an optional message string, charges $0.001 USDC via x402 micropayment, and returns a JSON echo of the input — a reference implementation of the x402 payment + CDP Facilitator + Bazaar discovery loop.

## Facts

- Endpoint: POST https://app.heinrichstech.com/v1/cdp/echo?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Last successful call: 2026-07-01
- Success rate: 50% of calls made through Zero
- Rating: 5.0 / 5 from 1 review
- Activations on Zero: 2
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bitbooth-echo-endpoint-x402-626e0bfa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_K1RideJGflHiACTEb8WMf

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 bitbooth-echo-endpoint-x402-626e0bfa -d '<json body>'
```

Example prompt: Send a test message through the BitBooth x402 echo endpoint — use the message 'hello from my agent' — so I can confirm my micropayment flow is working end to end.

## When to prefer this

Use this endpoint when you need to test or demonstrate an end-to-end x402 micropayment flow, validate that your CDP Facilitator integration and Bazaar discovery setup work correctly, or when you need a minimal, low-cost (< $0.01) reference call that confirms your agent can autonomously authorize and execute a pay-per-call API transaction.

## Known failure modes

- Insufficient USDC balance — payment fails, 402 Payment Required returned
- Message exceeds 500 character limit — 400 Bad Request
- x402 payment header malformed or missing — 402 or 400 error
- CDP Facilitator unavailable — service timeout or 503
- Network error during payment settlement — transaction may not confirm

## How this service works

BitBooth echo endpoint — pays a tiny USDC fee, returns a JSON echo. Reference implementation of the x402 + CDP Facilitator + Bazaar discovery loop.

## Output

A JSON object echoing back the submitted message string, confirming both the x402 USDC micropayment of $0.001 was processed and the request completed successfully through the CDP Facilitator and Bazaar discovery loop.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "message": {
   "type": "string",
   "maxLength": 500,
   "description": "Optional string to echo back in the response. Max 500 chars."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bitbooth-echo-endpoint-x402-626e0bfa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from app.heinrichstech.com](https://www.zero.xyz/host/app.heinrichstech.com/llms.txt)