# Grey Ridge Signals — Base Network Fee Estimator (x402)

> Grey Ridge Signals — Base Network Fee Estimator (x402) is a paid API for AI agents from x402-data-api.sigrunner.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-20).

Returns current Base network gas fee estimates (fast/standard/slow tiers) including base fee, priority fee, and ETH transfer cost, paid inline via x402 with no API key required.

## Facts

- Endpoint: GET https://x402-data-api.sigrunner.workers.dev/chain/fee-estimate?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/grey-ridge-signals-base-network-fee-estimator-x402-3e1295a4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_K3ZKtR-S8xMGlrrg7rlsq

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 grey-ridge-signals-base-network-fee-estimator-x402-3e1295a4
```

Example prompt: What are the current gas fees on Base — give me the fast, standard, and slow gwei tiers so I know what to set before submitting my transaction?

## When to prefer this

Choose this endpoint when an autonomous agent or trading bot needs real-time Base network gas fee data without an API key or account setup, especially when operating in a pay-per-call context using x402/USDC micropayments. Prefer this over Etherscan or Alchemy gas APIs when you want zero-friction, inline payment with no subscription overhead.

## Known failure modes

- Payment not settled (402): x402 payment not included or insufficient USDC
- RPC node unavailable: upstream Base node unreachable, returns 5xx
- Stale data: fee data may lag real-time chain state by a few seconds
- Invalid or missing parameters: non-Base chains not supported

## How this service works

Pay-per-call market & on-chain data for Base trading agents over x402: live DeFi yields, cross-venue funding rates, token prices, Polymarket and RPC data — plus a pre-trade token-safety gate (GO/HOLD/BLOCK). No account, no API key; agents pay inline in USDC from $0.001/call.

## Output

A JSON object with the chain name ('base'), a tiers object containing fast/standard/slow max fee values in gwei, the current base fee in gwei, the current priority fee in gwei, and the estimated ETH cost for a standard transfer.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "chain": "base",
  "tiers": {
   "fast": {
    "max_fee_gwei": 0.02
   },
   "slow": {
    "max_fee_gwei": 0.008
   },
   "standard": {
    "max_fee_gwei": 0.012
   }
  },
  "base_fee_gwei": 0.006,
  "priority_fee_gwei": 0.001,
  "transfer_cost_eth": {
   "standard": 2.5e-7
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/grey-ridge-signals-base-network-fee-estimator-x402-3e1295a4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-data-api.sigrunner.workers.dev](https://www.zero.xyz/host/x402-data-api.sigrunner.workers.dev/llms.txt)