# Delx Char Freq

> Delx Char Freq is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-16).

Computes character frequency distribution and top character histogram for a given text string

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/char-freq
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-char-freq-5a9fc39e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mbfqziYXA1TGXzeZkcQ7-

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-char-freq-5a9fc39e -d '<json body>'
```

Example prompt: What are the most frequent characters in this string, and how many unique ones are there? Text: 'the quick brown fox jumps over the lazy dog'

## When to prefer this

Use this endpoint when you need a lightweight, fast, local character-level frequency analysis prior to compression, encoding selection, or text profiling steps. It is ideal for agents that need to inspect text composition without any external data retention or third-party processing. Prefer it over heavier NLP endpoints when only character-level statistics (not word or semantic-level) are needed.

## Known failure modes

- Empty or missing text field — likely returns an error or empty histogram
- Extremely long strings may hit payload size limits
- Non-UTF-8 or binary input may produce unexpected character counts
- Network or payment failure via x402 protocol results in no response

## How this service works

Compute character frequency top counts. Call when you inspect distribution before encoding or compression steps. Returns unique count and top char histogram 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 the number of unique characters in the input text along with a histogram of the top characters by frequency, expressed as a local JSON object. No external network calls are made; results are computed in-process and returned immediately.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "top": [
   {
    "char": "b",
    "count": 3
   },
   {
    "char": "a",
    "count": 2
   },
   {
    "char": "c",
    "count": 1
   }
  ],
  "count": 6,
  "schema": "delx/util-char-freq/v1",
  "unique": 3
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-char-freq-5a9fc39e/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)