# Coin Flip (Cryptographically Random)

> Coin Flip (Cryptographically Random) is a paid API for AI agents from flat-rate-llm.kikoribera03.workers.dev, paid per call via x402, $0.0025/call, status unknown (last checked 2026-09-15).

Flips one or more fair coins using cryptographic randomness and returns each result (heads/tails) plus a tally of totals.

## Facts

- Endpoint: POST https://flat-rate-llm.kikoribera03.workers.dev/v1/random/coinflip
- Price: $0.0025/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/coin-flip-cryptographically-random-490237fa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dn9faiRHzm62kZqHwSdUh

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 coin-flip-cryptographically-random-490237fa -d '<json body>'
```

Example prompt: Flip 5 coins for me using a cryptographically random coin flip and tell me how many came up heads and how many came up tails.

## When to prefer this

Choose this endpoint when you need a verifiably fair, cryptographically random coin flip rather than a pseudo-random result from Math.random(). Ideal for tie-breaking, random binary decisions, probability simulations, or any context where fairness auditability matters. Supports batching up to 100 flips in a single call.

## Known failure modes

- count out of range (below 1 or above 100) returns an error
- non-integer or non-numeric count value may be rejected
- payment not attached or insufficient funds returns a 402 response
- network or worker timeout on the Cloudflare edge

## How this service works

60 paid endpoints with no metering, no API key and no account. Each endpoint has one flat price per call, whatever the size of the request: LLM completions with automatic failover across several large models, read-only EVM tooling over Base, Ethereum, Polygon, Arbitrum and Optimism, and pure crypto utilities that touch no network.

## Output

Returns a JSON object with the total count of coins flipped, an array of individual flip results (each item indicating heads or tails), the total number of heads, and the total number of tails.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "count": {
   "type": "number",
   "description": "How many coins to flip, 1-100. Defaults to 1."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "count": {
   "type": "number"
  },
  "flips": {
   "type": "array",
   "items": {
    "type": "object"
   }
  },
  "heads": {
   "type": "number"
  },
  "tails": {
   "type": "number"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/coin-flip-cryptographically-random-490237fa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from flat-rate-llm.kikoribera03.workers.dev](https://www.zero.xyz/host/flat-rate-llm.kikoribera03.workers.dev/llms.txt)