# fastapi.online — Generate Avatar

> fastapi.online — Generate Avatar is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.012/call, status unknown (last checked 2026-09-15).

Generates a unique avatar image from a text description of a person or character, with an optional seed for reproducibility.

## Facts

- Endpoint: POST https://api.fastapi.online/generate-avatar
- Price: $0.012/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastapi-online-generate-avatar-1c924d63
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VqxCw3gz7_TRhQbr6Wy6p

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 fastapi-online-generate-avatar-1c924d63 -d '<json body>'
```

Example prompt: Generate an avatar of a middle-aged male astronaut with a short beard and silver hair, use seed 42 so I can reproduce it later.

## When to prefer this

Choose this endpoint when you need a fast, cheap ($0.012 USDC), pay-per-call avatar image generated from a text description with no signup required. It is ideal when reproducibility via seed is important, or when you want a self-hosted model rather than a cloud provider. Best for agents that need on-demand avatar generation as part of a workflow without managing API keys or subscriptions.

## Known failure modes

- Description too short (minLength 1) or too long (maxLength 300) — validation error returned
- Invalid seed type (must be integer) — schema validation error
- Model inference failure or timeout — server error response
- Payment not completed or insufficient USDC — 402 Payment Required response
- Empty or missing description field — bad request error

## How this service works

Chat, embeddings, OCR, speech-to-text, image editing, image understanding (captioning/Q&amp;A), text-to-speech, translation, writing tools, classification tools, developer tools, local utilities, format/checksum validators, encoding &amp; crypto utilities, date/time calculators, geo/coordinate math, math &amp; finance calculators, novelty tools, and business/social writing generators — 179 endpoints in all, across multiple specialized self-hosted models. Pay per call with crypto — no signup — or get an API key.

## Output

Returns an avatar image (likely as binary image data or a URL) representing the described person or character, generated by a self-hosted AI image model. If a seed is provided, the same seed and description will reproduce the same avatar.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "seed": {
   "type": "integer"
  },
  "description": {
   "type": "string",
   "maxLength": 300,
   "minLength": 1,
   "description": "the person/character"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-generate-avatar-1c924d63/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.fastapi.online](https://www.zero.xyz/host/api.fastapi.online/llms.txt)