# Delx Mask Middle

> Delx Mask Middle 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).

Masks the middle characters of a string while preserving both ends, useful for redacting secrets in logs or displays.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/mask-middle
- 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-mask-middle-01cd13a5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PrEEEry-V52XZgVpJAKc1

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-mask-middle-01cd13a5 -d '<json body>'
```

Example prompt: Can you mask the middle of this API key so I can safely include it in a log — keep the first and last few characters visible: 'sk-abc123def456ghi789jkl'?

## When to prefer this

Choose this endpoint when you need a simple, cheap, stateless operation to redact the interior of a sensitive string for logging, display, or audit purposes, especially within an agentic pipeline where no external data retention or key management is acceptable. It is ideal for masking API keys, tokens, passwords, or card numbers in log lines or user-facing UIs without building custom string manipulation logic.

## Known failure modes

- Empty or missing 'text' field returns an error
- Very short strings (1-2 chars) may have no middle to mask, behavior may vary
- Network or payment authorization failure returns a 402 Payment Required response
- Malformed request body returns a 400 error

## How this service works

Mask the middle of a string keeping ends. Call when you redact secrets in logs while keeping identifiable edges. Returns masked text 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 masked version of the input string where the middle characters are replaced with masking characters (e.g. asterisks), with the original leading and trailing characters preserved, as a local JSON response with no data retention.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "text": "sk_li**********23456",
  "length": 20,
  "schema": "delx/util-mask-middle/v1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-mask-middle-01cd13a5/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)