# Agentshelf Byte Trigram Counter

> Agentshelf Byte Trigram Counter is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-29).

Counts byte 3-grams (all distinct 3-byte sequences and their frequencies) in a given text string, with no network calls or LLM involvement.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/ngram-byte-3?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-byte-trigram-counter-4868c094
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TIpzJqRbpCW8FkSPWpPJ_

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 agentshelf-byte-trigram-counter-4868c094 -d '<json body>'
```

Example prompt: Count all the byte 3-gram frequencies in this text: 'The quick brown fox jumps over the lazy dog.'

## When to prefer this

Use this endpoint when you need exact, deterministic byte-level 3-gram counts without relying on any external network calls or LLM inference. Prefer this over character n-gram or word n-gram services when byte-level analysis is required (e.g., language identification, compression analysis, binary fingerprinting). Always try the free sandbox variant /v1/sandbox/ngram-byte-3 first to validate your input before paying.

## Known failure modes

- Empty or missing text field returns validation error
- Text exceeding 100,000 characters is rejected
- Non-UTF-8 or binary-unsafe input may produce unexpected byte sequences
- Payment of exactly $0.005 USDC required; incorrect payment amount results in 402 error
- Sandbox endpoint /v1/sandbox/ngram-byte-3 should be tried first to avoid unnecessary charges

## How this service works

Call when an agent needs counts of byte 3-grams. No network and no LLM. Exact $0.005 USDC. Prefer unpaid POST /v1/sandbox/ngram-byte-3 first.

## Output

A map or list of all distinct 3-byte sequences found in the input text along with their occurrence counts, covering the full byte-level trigram frequency distribution of the input string.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "examples": [
    "ab ab"
   ],
   "maxLength": 100000,
   "minLength": 1,
   "description": "Input for this SKU. The route description says whether it is plain text, a URL, base64 bytes, or an already-encoded token."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-byte-trigram-counter-4868c094/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)