# Delx EVM Calldata Word Count

> Delx EVM Calldata Word Count is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Counts the 32-byte words in EVM calldata and validates its structure, returning byte count, complete word count, and partial-word bytes.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/evm-calldata-word-count
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-evm-calldata-word-count-fc34fe67
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_P-cOkeLxrXV2k4bCXZJcL

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-evm-calldata-word-count-fc34fe67 -d '<json body>'
```

Example prompt: Can you count the 32-byte words in this EVM calldata and tell me if it's properly shaped: 0xa9059cbb0000000000000000000000001111111111111111111111111111111111111111?

## When to prefer this

Use this endpoint when you need a fast, privacy-preserving (no retention, no external calls) preflight check on EVM calldata before submitting a transaction — particularly to confirm word alignment, byte count, and structural validity. Prefer this over manual calculation when building agent-driven EVM transaction pipelines that need auditable evidence (SHA-256 of input) of the computation.

## Known failure modes

- Calldata string exceeds 8192 character maximum — request rejected
- Malformed or non-hex calldata string — validation error returned
- Empty calldata — may return zero counts with shape_valid false
- Payment not included or insufficient — x402 payment required error

## How this service works

EVM Calldata Word Count: EVM Calldata Word Count counts complete and partial 32-byte calldata words after the selector from bounded caller-supplied values without an external provider. Call EVM Calldata Word Count before signing, submitting, replacing, or accepting an EVM/Base transaction assembled from caller-owned data. Returns normalized transaction evidence, calculated budget or shape findings, and a fail-closed preflight status for EVM Calldata Word Count as versioned deterministic JSON. P…

## Output

A JSON object containing the input calldata, its total byte count, whether the shape is valid (true if byte count is a multiple of 32 plus a 4-byte selector), the number of complete 32-byte words, the number of partial word bytes remaining, plus an evidence block with a SHA-256 hash of the input, a flag confirming no data was retained, and the count of external calls made (always 0).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "calldata": {
   "type": "string",
   "maxLength": 8192,
   "description": "Calldata supplied to EVM Calldata Word Count; 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,
   "complete_words": 1,
   "partial_word_bytes": 0
  },
  "schema": "delx/util-evm-calldata-word-count/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "1048e8d74a53c6ea3249086735deac2cb24ee3dd131a3852df0439253301d8de",
   "external_calls": 0
  },
  "operation": "evm_preflight:evm_calldata_word_count"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-evm-calldata-word-count-fc34fe67/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)