# md.fastdb.in Gas Price Oracle

> md.fastdb.in Gas Price Oracle is a paid API for AI agents from md.fastdb.in, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Returns live gas data for Ethereum, Base, Arbitrum, Optimism, and Polygon — including base fee, priority fee tiers (slow/standard/fast), and USD transfer cost pulled directly from chain RPC.

## Facts

- Endpoint: POST https://md.fastdb.in/pulse/gas
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/md-fastdb-in-gas-price-oracle-86ab6feb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_O_u9Z7v-GDW2wzh3WXa8D

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 md-fastdb-in-gas-price-oracle-86ab6feb -d '<json body>'
```

Example prompt: What are the current gas fees on Base right now — give me the base fee, the fast priority fee in gwei, and how much a simple ETH transfer would cost in USD?

## When to prefer this

Prefer this endpoint when you need real-time, multi-chain gas data from live RPC nodes rather than third-party aggregators, especially when you need both gwei-denominated fees and USD cost estimates in a single call. Ideal for agents making transaction cost decisions, displaying gas to users, or automating DeFi workflows that are cost-sensitive across multiple EVM chains.

## Known failure modes

- Unsupported chain name returns error or empty gas object
- RPC node temporarily unavailable causing stale or missing data
- Network congestion may cause slight lag in fee data
- Invalid POST body format returns 400 error
- Chain field missing from request may default to one chain or return error

## How this service works

Live gas on Ethereum, Base, Arbitrum, Optimism, Polygon — base fee, priority fee tiers, and USD transfer cost, straight from chain RPC.

## Output

Returns a JSON object with a timestamp, the queried chain(s), native token USD price, current base fee in gwei, gas price in gwei, slow/standard/fast priority fee tiers in gwei, and the estimated USD cost of a standard ETH transfer for each requested chain.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "at": "2026-07-17T15:00:00.000Z",
  "gas": {
   "base": {
    "chain": "base",
    "nativeUsd": 1818.32,
    "baseFeeGwei": 0.005,
    "blockNumber": 48755195,
    "priorityFee": {
     "fastGwei": 0.019,
     "slowGwei": 0.0001,
     "standardGwei": 0.0011
    },
    "gasPriceGwei": 0.006,
    "nativeSymbol": "ETH",
    "transferCostUsd": 0.0002291
   }
  },
  "chains": [
   "base"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/md-fastdb-in-gas-price-oracle-86ab6feb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from md.fastdb.in](https://www.zero.xyz/host/md.fastdb.in/llms.txt)