# RadhikaChain POI — Point-of-Interest Chain Telemetry

> RadhikaChain POI — Point-of-Interest Chain Telemetry is a paid API for AI agents from x402.radhikatmosphere.com, paid per call via x402, $1.716/call, status unknown (last checked 2026-09-15).

Returns a verifiable Merkle root, block height, and leaf count for a blockchain chain state checkpoint, enabling cryptographic proof-of-integrity for on-chain data.

## Facts

- Endpoint: POST https://x402.radhikatmosphere.com/poi
- Price: $1.716/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/radhikachain-poi-point-of-interest-chain-telemetry-56782d51
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Kn6MXGIXQTPL7mhQW7q0p

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 radhikachain-poi-point-of-interest-chain-telemetry-56782d51 -d '<json body>'
```

Example prompt: Can you fetch the latest verified chain state from RadhikaChain — I need the current Merkle root, block height, and leaf count as a cryptographic checkpoint?

## When to prefer this

Choose this endpoint when you need a cryptographically verifiable, pay-per-use chain state snapshot (Merkle root + block height) without requiring account registration or subscription — especially in ZK proof pipelines using Halo2, Nova, or Plonky3, or when auditing on-chain data integrity on Base. Prefer over subscription-based RPC providers when you need occasional, accountless, micropayment-gated chain telemetry.

## Known failure modes

- 402 Payment Required — x402 payment header missing or insufficient USDC amount
- Invalid payment — wrong chain (must be Base eip155:8453) or wrong token (must be native USDC)
- 503/timeout — chain telemetry service temporarily unavailable
- Malformed response if chain state is mid-update
- Payment facilitator rejection if x402 scheme version mismatch (must be v2 exact)

## How this service works

Telemetria de cadena, inteligencia de defensa y computo verificable (Halo2, Nova, Plonky3). Pago por peticion en USDC nativo en Base (eip155:8453) mediante x402 v2 scheme exact; sin cuenta ni suscripcion. Catalogo canonico: GET /.well-known/x402.

## Output

A JSON object containing: a Merkle root hash string (cryptographic fingerprint of chain state), the current block height (integer), and the total leaf count in the Merkle tree (integer). Example: {root: 'e96b3eac15c5...', height: 45058, leaves: 2}.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "body": {
     "type": "object",
     "additionalProperties": true
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": true
    }
   }
  },
  "output": {
   "type": "object",
   "properties": {
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "root": "e96b3eac15c5...",
  "height": 45058,
  "leaves": 2
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/radhikachain-poi-point-of-interest-chain-telemetry-56782d51/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.radhikatmosphere.com](https://www.zero.xyz/host/x402.radhikatmosphere.com/llms.txt)