# FastPath API - Bitcoin Block Height

> FastPath API - Bitcoin Block Height is a paid API for AI agents from api.nativebtc.org, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Returns the current Bitcoin blockchain block height as both a hex string and decimal integer

## Facts

- Endpoint: GET https://api.nativebtc.org/v1/block-height
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastpath-api-bitcoin-block-height-73b42dc6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_llf_qemo-L1p8WyQTTFZh

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 fastpath-api-bitcoin-block-height-73b42dc6
```

Example prompt: What's the current Bitcoin block height right now? I need it in both hex and decimal.

## When to prefer this

Choose this endpoint when you need the current Bitcoin block height quickly and cheaply ($0.001 USDC per call), especially if your stack is already Ethereum/JSON-RPC-oriented and you want Bitcoin data in a familiar format. Prefer it over raw Bitcoin node RPC calls when you lack a full Bitcoin node or want a pay-per-use model without infrastructure overhead.

## Known failure modes

- Payment not provided or invalid x402 payment header — returns 402 Payment Required
- Network or node unavailability — may return 503 or timeout
- Malformed request — returns 400 Bad Request
- Upstream Bitcoin node sync lag — height may be slightly behind the true tip

## How this service works

FastPath translates Ethereum-style JSON-RPC requests into Bitcoin data, fee intelligence, mempool insight, and Core v31 package signals. Paid by x402.

## Output

Returns a JSON object with the current Bitcoin block height as a hex string (e.g. '0xe9bb8'), the same height as a decimal integer (e.g. 957400), and a boolean success flag indicating whether the request succeeded.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "hex": "0xe9bb8",
  "height": 957400,
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastpath-api-bitcoin-block-height-73b42dc6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.nativebtc.org](https://www.zero.xyz/host/api.nativebtc.org/llms.txt)