# x402.valkyry.fr Gas Estimator

> x402.valkyry.fr Gas Estimator is a paid API for AI agents from x402.valkyry.fr, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Returns current gas price data (in Wei and Gwei) for a specified EVM-compatible network such as Base, Ethereum, Arbitrum, Optimism, or Polygon.

## Facts

- Endpoint: POST https://x402.valkyry.fr/gas?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-valkyry-fr-gas-estimator-e12257f7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Y9Y5T1WRtbuxsq3dWVuZL

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 x402-valkyry-fr-gas-estimator-e12257f7 -d '<json body>'
```

Example prompt: What's the current gas price on the Base network — give me both the Wei and Gwei values?

## When to prefer this

Use this endpoint when an AI agent needs real-time gas price data for EVM-compatible chains (Base, Ethereum, Arbitrum, Optimism, Polygon) in a pay-per-call model via x402/USDC, without needing a full RPC provider subscription. Ideal for lightweight, single-call gas checks embedded in automated workflows.

## Known failure modes

- Unsupported network string returns an error or defaults to Ethereum
- Network RPC unavailable causes timeout or 5xx error
- Stale gas data if underlying node is behind chain tip
- Invalid input type for 'network' field returns validation error

## How this service works

Current gas price (gwei) on Ethereum, Base, Arbitrum, Optimism or Polygon. Lets agents time and price on-chain transactions.

## Output

A JSON object containing the EIP-155 network identifier (e.g. 'eip155:1'), the current gas price in Wei as a string, and the current gas price in Gwei as a decimal number.

## Example request

```json
{
 "network": "base"
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "network": {
   "type": "string",
   "description": "ethereum | base | arbitrum | optimism | polygon (default ethereum)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "network": "eip155:1",
  "gasPriceWei": "12300000000",
  "gasPriceGwei": "12.3"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-valkyry-fr-gas-estimator-e12257f7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.valkyry.fr](https://www.zero.xyz/host/x402.valkyry.fr/llms.txt)