# Chainlink Oracle Freshness Probe

> Chainlink Oracle Freshness Probe is a paid API for AI agents from meryol-agenticmarket-x402.hf.space, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Probes a Chainlink oracle feed on EVM chains via eth_call to latestRoundData(), returning staleness, scaled answer, and a safety flag for lending/AMM agents

## Facts

- Endpoint: GET https://meryol-agenticmarket-x402.hf.space/oracle/freshness/:chain/:feed
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/meryol-agenticmarket-x402-hf-space-83700af5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_90npN3iZW42h4C27Zk678

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 meryol-agenticmarket-x402-hf-space-83700af5
```

Example prompt: Before I trigger this borrow on Arbitrum, can you check whether the Chainlink ETH/USD feed at 0x639Fe6ab55C921f74e7fac1ee960C0B6293ba612 is fresh and safe to use — give me the staleness in seconds and whether it's safe?

## When to prefer this

Use this endpoint when an AI agent or DeFi protocol needs to verify Chainlink oracle freshness before executing any oracle-dependent action such as borrowing, liquidating, or swapping on Ethereum, Base, Arbitrum, or Optimism. Prefer this over generic RPC calls when you need a structured staleness judgment (is_safe_to_use boolean) rather than raw on-chain data.

## Known failure modes

- Invalid feed address format (not a valid 0x EVM address) — 400 error
- Unsupported chain name (not one of ethereum/base/arbitrum/optimism) — 400 or validation error
- Feed address does not correspond to a Chainlink oracle on the specified chain — RPC call failure or null response
- RPC unavailable for the target chain — upstream timeout or 503
- Payment not provided or insufficient — 402 Payment Required

## How this service works

Pre-execution oracle staleness check: direct eth_call to a Chainlink aggregator's latestRoundData(). feed = 0x-address OR alias (eth-usd, btc-usd, usdc-usd). Returns scaled answer, updated_at, staleness vs the feed's real heartbeat, and is_safe_to_use. Call before borrows or oracle-dependent execution. Chains: ethereum, base, arbitrum, optimism.

## Output

Returns feed description, decimals, scaled price answer, updated_at timestamp, staleness in seconds since last update, and an is_safe_to_use boolean indicating whether the oracle data is fresh enough to act on.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "pathParams": {
   "feed": "0x639Fe6ab55C921f74e7fac1ee960C0B6293ba612",
   "chain": "ethereum"
  },
  "queryParams": {}
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "chain",
      "feed"
     ],
     "properties": {
      "feed": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$"
      },
      "chain": {
       "enum": [
        "ethereum",
        "base",
        "arbitrum",
        "optimism"
       ],
       "type": "string"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "is_safe_to_use",
      "staleness_seconds"
     ]
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/meryol-agenticmarket-x402-hf-space-83700af5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from meryol-agenticmarket-x402.hf.space](https://www.zero.xyz/host/meryol-agenticmarket-x402.hf.space/llms.txt)