# Rubric Protocol – Attested Hedera Staking Facts

> Rubric Protocol – Attested Hedera Staking Facts is a paid API for AI agents from rubric-protocol.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Returns a post-quantum-attested snapshot of Hedera network staking data (node roster, staking rates, and related facts) with an ML-DSA-65 attestation ID proving tamper-evident provenance.

## Facts

- Endpoint: GET https://rubric-protocol.com/v1/x402/hedera-facts/staking
- 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/rubric-protocol-attested-hedera-staking-facts-fc99487b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_je0x2hijQIjkHQpAM0zRI

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 rubric-protocol-attested-hedera-staking-facts-fc99487b
```

Example prompt: Fetch me the latest attested Hedera staking facts — I need the node roster and staking data with the ML-DSA-65 attestation ID so I can prove exactly what data I relied on when making this decision.

## When to prefer this

Choose this endpoint when your agent needs cryptographically provable, tamper-evident Hedera staking data — especially in compliance, audit, or decision-tracing contexts where you must prove exactly what network facts were observed at the time of action. It is preferable over raw RPC or unattested data feeds when post-quantum signature attestation (ML-DSA-65) is required as evidence.

## Known failure modes

- Payment not received or invalid x402 payment header — returns 402 Payment Required
- Hedera network temporarily unavailable — snapshot may be stale or endpoint returns 503
- Invalid or malformed GET request — returns 400 Bad Request
- Rate limiting exceeded — returns 429 Too Many Requests
- Attestation service temporarily unavailable — may return partial data without attestation ID

## How this service works

Attested Hedera network facts: HBAR exchange rate, gas fees, supply, node roster, throughput, topic state. Each response

## Output

A structured JSON snapshot of Hedera network staking facts — including node roster, staking rates, HBAR exchange rate, gas fees, token supply, throughput, and topic state — accompanied by an ML-DSA-65 (post-quantum) attestation ID that cryptographically anchors the snapshot and proves its contents have not been tampered with.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "fact"
     ],
     "properties": {
      "fact": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "format": {
     "type": "string"
    },
    "example": {}
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/rubric-protocol-attested-hedera-staking-facts-fc99487b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rubric-protocol.com](https://www.zero.xyz/host/rubric-protocol.com/llms.txt)