# Delx Is Hex Shape

> Delx Is Hex Shape is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Validates whether a string is a properly formed even-length hexadecimal value (with optional 0x prefix)

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/is-hex-shape
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-is-hex-shape-2dbe2a42
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dDu3nthMqwGKdu89nGtKA

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-is-hex-shape-2dbe2a42 -d '<json body>'
```

Example prompt: Before sending this calldata to the chain tool, can you check if '0x1a2b3c4d' is a valid even-length hex string?

## When to prefer this

Use this endpoint when you need a fast, stateless, no-key preflight check on a hex string before passing it to blockchain or cryptographic tools. It is ideal for input sanitization pipelines where you want to catch malformed calldata or hash strings early, without spinning up any network or chain connection. Prefer this over building custom regex validation when operating in an agentic workflow that already uses x402 micropayment rails.

## Known failure modes

- Missing or empty hex input field returns an error
- Odd-length hex strings return valid: false
- Non-hex characters (like 'G', 'Z') cause valid: false
- Malformed request body returns HTTP 400
- Payment not included or rejected returns HTTP 402

## How this service works

Validate even-length hex (optional 0x). Call when you preflight calldata/hash hex before chain tools. Returns valid boolean for $0.001 USDC via x402 on Base. No network, no keys, no retention; first-party local JSON only. Results are advisory; the caller owns budgets, auth, and production controls.

## Output

Returns a JSON object containing a boolean 'valid' field indicating whether the input string is a properly formed even-length hexadecimal value, optionally prefixed with '0x'. No additional data is retained or returned.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "hex": {
   "type": "string",
   "description": "Input field: hex."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "hex": "0xffaa",
  "valid": true,
  "schema": "delx/util-is-hex-shape/v1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-is-hex-shape-2dbe2a42/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)