# Polygon PoS Gas Conditions API

> Polygon PoS Gas Conditions API is a paid API for AI agents from ca-tax-api-mainnet.lxtap.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-23).

Returns current Polygon PoS network gas conditions including block number, base fee, gas price, priority fee in gwei, and estimated transfer costs in POL and USD.

## Facts

- Endpoint: GET https://ca-tax-api-mainnet.lxtap.workers.dev/polygon/gas?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polygon-pos-gas-conditions-api-2f8c5781
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aXIdsc9Js5n3UBBYbwa4u

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 polygon-pos-gas-conditions-api-2f8c5781
```

Example prompt: What are the current gas fees on Polygon PoS right now — give me the base fee, gas price, priority fee in gwei, and how much a native POL transfer and an ERC-20 transfer would cost in both POL and USD?

## When to prefer this

Choose this endpoint when you need real-time Polygon PoS gas fee data including USD cost estimates for both native POL transfers and ERC-20 token transfers. It is particularly useful for DeFi bots, wallet UIs, and pre-transaction cost checks on Polygon. Prefer this over generic gas APIs when you specifically need POL/USD converted costs backed by a Chainlink oracle.

## Known failure modes

- Chainlink oracle unavailability may cause stale or missing USD price data
- Polygon RPC node downtime could cause request failures or stale block data
- High network congestion may result in rapidly outdated gas estimates by the time they are used
- HTTP 402 payment required if the x402 payment header is missing or insufficient

## How this service works

Pay-per-call data for AI agents, paid in USDC on Base with x402: token risk checks (rug check) on Base, Ethereum, Arbitrum, Optimism, Polygon and Solana, onchain reads (balances, transactions, gas, contracts, NFTs, whale trades, new pools, ENS and Basenames), ECB exchange rates, and Canadian sales tax and business days.

## Output

Returns a JSON object containing the current Polygon PoS block number, base fee in gwei, gas price in gwei, priority fee in gwei, estimated cost of a native POL transfer in both POL and USD, and estimated cost of an ERC-20 transfer in both POL and USD (using the Chainlink POL/USD price feed).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "required": {
   "type": "string"
  },
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "chain": "polygon",
  "blockTime": "2026-10-22T15:50:44.000Z",
  "nativeUsd": 0.0905823,
  "baseFeeGwei": "248.763643361",
  "blockNumber": 95985915,
  "gasPriceGwei": "276.772562084",
  "nativeSymbol": "POL",
  "estimatedCost": {
   "erc20Transfer": {
    "usd": 0.00163,
    "native": "0.01799021653546"
   },
   "nativeTransfer": {
    "usd": 0.0005265,
    "native": "0.005812223803764"
   }
  },
  "maxPriorityFeeGwei": "28.008918723"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polygon-pos-gas-conditions-api-2f8c5781/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ca-tax-api-mainnet.lxtap.workers.dev](https://www.zero.xyz/host/ca-tax-api-mainnet.lxtap.workers.dev/llms.txt)