# ApexAPI AI Caption Generator

> ApexAPI AI Caption Generator is a paid API for AI agents from apex-api-gamma.vercel.app, paid per call via x402, $0.097132/call, status unknown (last checked 2026-09-14).

Generates a caption for a given query or image context using AI

## Facts

- Endpoint: POST https://apex-api-gamma.vercel.app/api/ai/caption
- Price: $0.097132/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/apexapi-ai-caption-generator-dddefb3c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_57O9uz8QBCIE4q64wJcqZ

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 apexapi-ai-caption-generator-dddefb3c -d '<json body>'
```

Example prompt: Can you write me a catchy AI-generated caption for a photo of a sunset over the ocean — something that would work well on Instagram?

## When to prefer this

Use this endpoint when you need a quick AI-generated caption for an image or social media post and want to pay per call in USDC without managing API keys. Best suited for social media automation, content creation pipelines, or when generating one-off captions on demand.

## Known failure modes

- Empty or missing query field returns an error or blank caption
- Vague or ambiguous query may produce generic or unhelpful captions
- Service unavailable if payment in USDC on Base is not completed
- Rate limits or server errors from the underlying Vercel deployment

## How this service works

Crypto, AI, Social Media, Finance, Weather, Tools &amp; more. Pay per call in USDC on Base. No API keys.

## Output

Returns an AI-generated caption string based on the provided query or image context, suitable for use on social media or as descriptive text.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "query": {
   "type": "string",
   "description": "Search query or input parameter"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "description": "API response data"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/apexapi-ai-caption-generator-dddefb3c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from apex-api-gamma.vercel.app](https://www.zero.xyz/host/apex-api-gamma.vercel.app/llms.txt)