# Ethereum Gas Telemetry

> Ethereum Gas Telemetry is a paid API for AI agents from api.chainmarket-api.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Returns per-block Ethereum gas fee telemetry including base fee, gas used ratio, and priority fee percentiles for recent blocks

## Facts

- Endpoint: GET https://api.chainmarket-api.workers.dev/api/crypto/ethereum-gas-telemetry?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ethereum-gas-telemetry-03aa9548
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Wm_6-73c33ulc-4pHb7a3

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 ethereum-gas-telemetry-03aa9548
```

Example prompt: What are the current Ethereum gas fees — show me base fee, priority fee percentiles, and the expected next base fee across the last 5 blocks so I can decide whether to submit my transaction now.

## When to prefer this

Choose this endpoint when you need real-time Ethereum gas fee data across multiple recent blocks with percentile-level priority fee breakdown (p10/p50/p90) and next-base-fee prediction — without requiring an API key or signup. Prefer this over raw RPC calls when you want pre-parsed, structured gas telemetry with no infrastructure setup, paying only $0.002 USDC per call via x402.

## Known failure modes

- Invalid blockCount value (outside 1-20 range) may return an error or be clamped to defaults
- Upstream PublicNode RPC unavailability could cause a failed fetch — no charge on failure
- Stale data if the public RPC node is lagging behind chain head
- Network timeout if the Cloudflare Worker or upstream RPC is slow

## How this service works

Ethereum EIP-1559 gas per recent block: base fee (gwei), gas used ratio, and priority fee (tip) percentiles at 10/50/90 from eth_feeHistory, plus the next block's base fee. Gas used by contract is not included (this RPC does not give it).

## Output

Returns a JSON object containing an array of recent blocks (up to 20), each with blockNumber, baseFeeGwei, gasUsedRatioPct, and priorityFeeGwei percentiles (p10, p50, p90). Also includes nextBaseFeeGwei (the projected next base fee), total blockCount, oldestBlock number, the source RPC URL, and a checkedAt ISO timestamp.

## 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": {
      "blockCount": {
       "type": "string",
       "description": "How many recent blocks, 1 to 20 (default 5)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "blocks": [
   {
    "baseFeeGwei": 0.071402703,
    "blockNumber": 26254462,
    "gasUsedRatioPct": 28.83,
    "priorityFeeGwei": {
     "p10": 0.001,
     "p50": 0.02656767,
     "p90": 1
    }
   },
   {
    "baseFeeGwei": 0.067623505,
    "blockNumber": 26254463,
    "gasUsedRatioPct": 26.15,
    "priorityFeeGwei": {
     "p10": 0.000002456,
     "p50": 0.00029472,
     "p90": 1
    }
   }
  ],
  "source": "https://ethereum-rpc.publicnode.com",
  "checkedAt": "2026-10-23T09:35:54.739Z",
  "blockCount": 5,
  "oldestBlock": 26254462,
  "nextBaseFeeGwei": 0.06955529
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ethereum-gas-telemetry-03aa9548/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.chainmarket-api.workers.dev](https://www.zero.xyz/host/api.chainmarket-api.workers.dev/llms.txt)