# EIP-1559 Fee Suggestion

> EIP-1559 Fee Suggestion is a paid API for AI agents from flat-rate-llm.kikoribera03.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns suggested maxFeePerGas and maxPriorityFeePerGas at slow, normal, and fast percentiles derived from the last 20 blocks of real fee history, plus the current base fee.

## Facts

- Endpoint: POST https://flat-rate-llm.kikoribera03.workers.dev/v1/evm/fees
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/eip-1559-fee-suggestion-828170e3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_a1iO3aYLoD_r_7HzrA-Pg

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 eip-1559-fee-suggestion-828170e3 -d '<json body>'
```

Example prompt: What EIP-1559 gas fees should I use right now — give me the maxFeePerGas and maxPriorityFeePerGas at normal speed so my transaction gets confirmed without overpaying?

## When to prefer this

Choose this endpoint when you need EIP-1559-compatible fee parameters (maxFeePerGas + maxPriorityFeePerGas) grounded in real recent block history rather than a single gas price guess. It is ideal for agents building or broadcasting transactions on Base, Ethereum, Polygon, Arbitrum, or Optimism who want tiered slow/normal/fast options without implementing eth_feeHistory parsing themselves.

## Known failure modes

- RPC node unavailable or rate-limited — may return 5xx or empty response
- Chain congestion causing fee history to be unusually volatile, making percentile suggestions less reliable
- No required parameters means little room for input errors, but stale data is possible if the upstream node lags

## How this service works

60 paid endpoints with no metering, no API key and no account. Each endpoint has one flat price per call, whatever the size of the request: LLM completions with automatic failover across several large models, read-only EVM tooling over Base, Ethereum, Polygon, Arbitrum and Optimism, and pure crypto utilities that touch no network.

## Output

A JSON object containing three fee tiers (slow, normal, fast), each with maxFeePerGas and maxPriorityFeePerGas in wei as strings, plus a top-level baseFeeWei field reflecting the current base fee derived from the last 20 blocks of on-chain fee history.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string",
   "description": "base | ethereum | polygon | arbitrum | optimism."
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/eip-1559-fee-suggestion-828170e3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from flat-rate-llm.kikoribera03.workers.dev](https://www.zero.xyz/host/flat-rate-llm.kikoribera03.workers.dev/llms.txt)