# Delx Commerce — Content-Type Sniff

> Delx Commerce — Content-Type Sniff is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Heuristically detects the MIME content type of a file or data sample based on filename and/or byte sample

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/content-type-sniff?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-content-type-sniff-eabf1360
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_V1Zn72A_biXrx4Ilk4n8r

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-commerce-content-type-sniff-eabf1360 -d '<json body>'
```

Example prompt: What's the MIME type of a file named 'doc.pdf' — can you sniff the content type from the filename and the first few bytes?

## When to prefer this

Use this endpoint when you need a fast, cheap ($0.001 USDC), no-signup content-type detection utility for agent workflows — especially when handling untrusted file uploads, routing files to parsers, or validating file formats before processing. Prefer this over full MIME database lookups when heuristic confidence is sufficient and low latency is important.

## Known failure modes

- Missing both filename and sample may result in low-confidence or unknown content type
- Very short or ambiguous byte samples reduce detection accuracy
- Exotic or rare MIME types may not be in the local heuristic database
- Malformed input JSON returns an error response

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with the detected MIME content type (e.g. 'application/pdf'), a confidence indicator (heuristic), the filename used for inference, the number of sample bytes analyzed, a note about the local sniff scope, and a schema identifier (delx/util-content-type-sniff/v1).

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "note": "local sniff only; not full MIME database",
  "schema": "delx/util-content-type-sniff/v1",
  "filename": "doc.pdf",
  "confidence": "heuristic",
  "content_type": "application/pdf",
  "sample_bytes": 13
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-content-type-sniff-eabf1360/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)