# b0x402-data Multi-Chain Gas Tracker

> b0x402-data Multi-Chain Gas Tracker is a paid API for AI agents from b0x402-data.mulberry-boar.workers.dev, paid per call via x402, $0.4/call, status unknown (last checked 2026-09-15).

Returns real-time EVM gas prices (slow/avg/fast tiers) for a specified blockchain network, paid per call via x402 USDC micropayment.

## Facts

- Endpoint: GET https://b0x402-data.mulberry-boar.workers.dev/v1/gas-tracker
- Price: $0.4/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/b0x402-data-multi-chain-gas-tracker-a8fdd8af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_axtHc5qtNsV0CgrQfW_X1

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 b0x402-data-multi-chain-gas-tracker-a8fdd8af
```

Example prompt: What are the current slow, average, and fast gas prices on Ethereum right now — I want to know if it's a good time to send a transaction?

## When to prefer this

Use this endpoint when you need real-time, tiered gas price data (slow/avg/fast) across multiple EVM chains in a single call, especially when building transaction cost estimators, DeFi bots, or wallet UX that needs current on-chain fee data. Prefer over free alternatives when reliability and freshness of actual RPC data matters, and when operating in a pay-per-call x402 micropayment context on Base.

## Known failure modes

- Missing or invalid 'chain' query parameter — endpoint requires one of the supported enum values
- Unsupported chain name provided — only ethereum, base, arbitrum, optimism, polygon, bsc are accepted
- Upstream RPC node unavailable — may return 502 or error response
- Payment not received or invalid x402 USDC payment — call rejected with 402 status
- Rate limiting or worker timeout on Cloudflare edge

## How this service works

Real-data x402 V2 API on Base. Token safety scanner (Honeypot.is + on-chain) and multi-chain gas tracker. Pay per call in USDC.

## Output

Returns the chain identifier, numeric chain ID, current base fee in wei and gwei, three gas price tiers (slow at 25th percentile, avg at 50th percentile, fast at 75th percentile) in gwei, an ISO timestamp of when data was fetched, the upstream RPC source, and an estimated USD cost for a standard 21,000-gas transfer.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "queryParams": {
     "type": "object",
     "required": [
      "chain"
     ],
     "properties": {
      "chain": {
       "enum": [
        "ethereum",
        "base",
        "arbitrum",
        "optimism",
        "polygon",
        "bsc"
       ],
       "type": "string",
       "default": "ethereum",
       "description": "EVM chain identifier"
      }
     },
     "additionalProperties": true
    }
   },
   "additionalProperties": true
  },
  "output": {
   "type": "object",
   "required": [
    "chain",
    "gas_price_wei",
    "gas_price_gwei",
    "tiers",
    "timestamp"
   ],
   "properties": {
    "chain": {
     "type": "string",
     "description": "Chain identifier"
    },
    "tiers": {
     "type": "object",
     "required": [
      "slow",
      "avg",
      "fast"
     ],
     "properties": {
      "avg": {
       "type": "number",
       "description": "50th-percentile priority + base, in gwei"
      },
      "fast": {
       "type": "number",
       "description": "75th-percentile priority + base, in gwei"
      },
      "slow": {
       "type": "number",
       "description": "25th-percentile priority + base, in gwei"
      }
     },
     "additionalProperties": true
    },
    "source": {
     "type": "string",
     "description": "Upstream RPC identifier"
    },
    "chain_id": {
     "type": "integer",
     "description": "Numeric chainId"
    },
    "timestamp": {
     "type": "string",
     "description": "Fetch timestamp ISO"
    },
    "gas_price_wei": {
     "type": "string",
     "description": "Latest block base-fee in wei (string to preserve precision)"
    },
    "gas_price_gwei": {
     "type": "number",
     "description": "Equals value in gwei"
    },
    "eth_price_usd_equiv": {
     "type": "number",
     "description": "Estimated USD for a 21000-gas transfer (1 gwei worth assumption)"
    }
   },
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "chain": "ethereum",
 "tiers": {
  "avg": "0.18",
  "fast": "0.22",
  "slow": "0.16"
 },
 "timestamp": "ISO",
 "gas_price_wei": "144778303",
 "gas_price_gwei": 0.145,
 "eth_price_usd_equiv": 0.04
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/b0x402-data-multi-chain-gas-tracker-a8fdd8af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from b0x402-data.mulberry-boar.workers.dev](https://www.zero.xyz/host/b0x402-data.mulberry-boar.workers.dev/llms.txt)