# Delx Commerce EVM EIP-1559 Fee Check

> Delx Commerce EVM EIP-1559 Fee Check is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Validates and computes the fee ceiling for an EVM EIP-1559 transaction given gas limit, max fee per gas, and max priority fee per gas in wei.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/evm-eip1559-fee-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-evm-eip-1559-fee-check-03d142a1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Pm90l13aGfjs8xs3Bl-3j

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 delx-commerce-evm-eip-1559-fee-check-03d142a1 -d '<json body>'
```

Example prompt: Before I submit this Ethereum transaction, check whether my EIP-1559 fee parameters are valid: gas limit is 21000, max fee per gas is 50000000000 wei, and max priority fee per gas is 2000000000 wei — tell me the fee ceiling and whether the caps are correctly ordered.

## When to prefer this

Use this endpoint when you need a fast, verifiable, pay-per-use EIP-1559 fee preflight check without setting up an account or running local computation. It is ideal for AI agents that need to validate gas fee parameters just before broadcasting an EVM transaction, especially when auditability (SHA-256 input hash, no data retention, zero external calls) is important. Prefer this over rolling your own calculation when you need the result to be independently verifiable.

## Known failure modes

- Invalid or non-integer gas_limit causes a validation error
- max_priority_fee_per_gas_wei exceeds max_fee_per_gas_wei results in fee_caps_ordered: false
- Malformed wei string (non-numeric) causes parse failure
- Missing required fields may result in a 400 Bad Request
- Payment failure via x402 protocol blocks the request

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with the computed fee_ceiling_wei (gas_limit × max_fee_per_gas_wei), priority_fee_ceiling_wei (gas_limit × max_priority_fee_per_gas_wei), and fee_caps_ordered (boolean indicating max_fee >= priority_fee), along with a status of 'pass' or 'fail', an SHA-256 hash of the input for auditability, and confirmation that no data was retained externally.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "gas_limit": {
   "type": "integer",
   "description": "Gas Limit supplied to EVM Eip1559 Fee Check; used only for this bounded calculation and processed in memory without retention."
  },
  "max_fee_per_gas_wei": {
   "type": "string",
   "maxLength": 8192,
   "description": "Max Fee Per Gas Wei supplied to EVM Eip1559 Fee Check; used only for this bounded calculation and processed in memory without retention."
  },
  "max_priority_fee_per_gas_wei": {
   "type": "string",
   "maxLength": 8192,
   "description": "Max Priority Fee Per Gas Wei supplied to EVM Eip1559 Fee Check; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "fee_ceiling_wei": "42000000000000",
   "fee_caps_ordered": true,
   "priority_fee_ceiling_wei": "2100000000000"
  },
  "schema": "delx/util-evm-eip1559-fee-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "09e6859a0243cf6df6f99d660a7735e0bfb2893802645cebf1d03fa659f21a65",
   "external_calls": 0
  },
  "operation": "evm_preflight:evm_eip1559_fee_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-evm-eip-1559-fee-check-03d142a1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)