# Delx Commerce Image Captioning API

> Delx Commerce Image Captioning API is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-02).

Generates a plain-text caption describing the visual content of a base64-encoded image, paid per-result via USDC

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/caption-image?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-image-captioning-api-22b6f812
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zdFKWb_bawcakGISP6Omj

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-image-captioning-api-22b6f812 -d '<json body>'
```

Example prompt: Can you caption this image for me? Here it is as a base64-encoded JPEG — just tell me what's in it.

## When to prefer this

Choose this endpoint when you need a quick, low-cost, no-signup image captioning call paid per result with on-chain verifiability via USDC. Ideal for AI agents operating autonomously without pre-negotiated API keys, or when you need pay-as-you-go billing with cryptographic payment proof. Best suited for single-image captioning of PNG, JPEG, or WebP files under 256 KiB.

## Known failure modes

- Image exceeds 256 KiB decoded size — request rejected
- Invalid base64 encoding — returns error
- Unsupported image format (not PNG, JPEG, or WebP) — request rejected
- URL passed instead of base64 data — explicitly rejected by schema
- Model field included — rejected
- Payment not provided or insufficient USDC — 402 Payment Required response
- Network timeout if image is at size limit

## How this service works

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

## Output

A JSON object containing a 'text' field with a natural language caption describing the image contents, and a 'sale_price_usdc' field confirming the per-call charge (e.g. 0.005 USDC).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "image_base64": {
   "type": "string",
   "maxLength": 349550,
   "minLength": 1,
   "description": "One base64-encoded PNG, JPEG, or WebP up to 256 KiB decoded. URLs and model fields are rejected."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "text": "a blue rectangle",
  "sale_price_usdc": 0.005
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-image-captioning-api-22b6f812/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)