# Orbit Chain Reads – EVM Gas Fees

> Orbit Chain Reads – EVM Gas Fees is a paid API for AI agents from orbit-chain.orbit-builder.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-29).

Returns live EIP-1559 gas fee estimates (slow/standard/fast) for Base, Ethereum, Arbitrum, Optimism, or Polygon, including next base fee, gas price, and priority fees in gwei.

## Facts

- Endpoint: GET https://orbit-chain.orbit-builder.workers.dev/v1/gas?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/orbit-chain-reads-evm-gas-fees-a0c55ae1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_j3k_piIAx6uVpby5N1Ckk

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 orbit-chain-reads-evm-gas-fees-a0c55ae1
```

Example prompt: What are the current slow, standard, and fast EIP-1559 gas fees on Base right now, including the next base fee and priority fees in gwei?

## When to prefer this

Use this endpoint when an agent or user needs live, EIP-1559-compatible gas estimates across major EVM chains without running their own node. Ideal for pre-transaction cost estimation, DeFi automation, gas monitoring bots, or cross-chain cost comparisons. Prefer over generic Web3 libraries when you need a single HTTP call with no wallet or provider setup.

## Known failure modes

- Invalid chain name returns an error or falls back to default (base)
- Public RPC node temporarily unavailable causes call failure
- Network timeout if RPC latency spikes
- Stale data if block production halts on the queried chain

## How this service works

Live EVM chain reads for agents across Base, Ethereum, Arbitrum, Optimism and Polygon: gas fees, wallet balances (native + USDC), transaction status, ERC-20 metadata and ENS resolution. Every answer is read from public RPC nodes at call time. $0.001 per call. By orbit-builder.

## Output

Returns a JSON object with the target chain name and chain ID, current block number, gas_price_gwei, base_fee_next_gwei, and nested slow/standard/fast objects each containing max_fee_gwei and max_priority_fee_gwei derived from the median of the last 20 blocks' 10th, 50th, and 90th percentile tips respectively.

## 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"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "chain": {
       "type": "string",
       "description": "base (default), ethereum, arbitrum, optimism, polygon, or all"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "fast": {
   "max_fee_gwei": 0.0178,
   "max_priority_fee_gwei": 0.01
  },
  "slow": {
   "max_fee_gwei": 0.0058,
   "max_priority_fee_gwei": 0.0001
  },
  "block": 37000000,
  "chain": "base",
  "chain_id": 8453,
  "standard": {
   "max_fee_gwei": 0.0075,
   "max_priority_fee_gwei": 0.001
  },
  "gas_price_gwei": 0.0061,
  "base_fee_next_gwei": 0.0052
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/orbit-chain-reads-evm-gas-fees-a0c55ae1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from orbit-chain.orbit-builder.workers.dev](https://www.zero.xyz/host/orbit-chain.orbit-builder.workers.dev/llms.txt)