# Delx Commerce — EVM Calldata Shape Check

> Delx Commerce — EVM Calldata Shape 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 the structural shape and byte count of EVM calldata without retaining or executing it

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/evm-calldata-shape-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-calldata-shape-check-6f190bcb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_N_tKLq1d32tyHIDQAg3LP

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-calldata-shape-check-6f190bcb -d '<json body>'
```

Example prompt: Can you do a shape check on this EVM calldata to make sure it's structurally valid before I submit it on-chain: 0xa9059cbb0000000000000000000000001111111111111111111111111111111111111111

## When to prefer this

Use this endpoint when you need a lightweight, stateless, pay-per-call structural validation of EVM calldata before submitting a transaction on-chain. It is ideal for agent pipelines performing preflight checks, since it guarantees no data retention, no external calls, and provides a verifiable SHA-256 evidence trail. Prefer it over general-purpose code execution or on-chain simulation tools when you only need to confirm calldata encoding shape and byte count.

## Known failure modes

- Calldata exceeds 8192 character limit — request rejected
- Non-hex or malformed string input — shape_valid returns false
- Payment failure via x402 — 402 response returned before processing
- Empty calldata field — may return validation error or shape_valid false

## 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 original calldata, byte count, a boolean shape_valid flag, the operation name, a status field ('pass' or 'fail'), and an evidence block confirming no data was retained, no external calls were made, and providing the SHA-256 hash of the input for auditability.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "calldata": {
   "type": "string",
   "maxLength": 8192,
   "description": "Calldata supplied to EVM Calldata Shape Check; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "calldata": "0xa9059cbb0000000000000000000000001111111111111111111111111111111111111111",
   "byte_count": 36,
   "shape_valid": true
  },
  "schema": "delx/util-evm-calldata-shape-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "1048e8d74a53c6ea3249086735deac2cb24ee3dd131a3852df0439253301d8de",
   "external_calls": 0
  },
  "operation": "evm_preflight:evm_calldata_shape_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-evm-calldata-shape-check-6f190bcb/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)