# fastapi.online Intent Classification

> fastapi.online Intent Classification is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.001/call, status down (last checked 2026-09-15).

Classifies a given text into one of several user-defined labels using self-hosted zero-shot or few-shot AI classification

## Facts

- Endpoint: POST https://api.fastapi.online/intent-classify
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastapi-online-intent-classification-d2c13cea
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4JjdcnIMsB5i4rKpLk0My

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-intent-classification-d2c13cea -d '<json body>'
```

Example prompt: Classify this customer message — 'My order arrived damaged and I want a refund' — into one of these labels: billing, shipping, return request, general inquiry. Tell me which label fits best.

## When to prefer this

Choose this endpoint when you need fast, pay-per-call zero-shot text classification without signup or subscription. Ideal for agents that need to route, tag, or categorize arbitrary text into custom label sets on-demand, especially when the label set changes per request. Prefer over OpenAI or Google NLP when you want crypto micropayment billing with no API key registration.

## Known failure modes

- Text below minimum length (< 1 char) returns validation error
- Fewer than 2 labels or more than 20 labels causes schema rejection
- Text exceeding 8000 characters is rejected
- Payment not sent or insufficient USDC triggers 402 Payment Required
- Model unavailability returns 5xx server error
- Ambiguous text may yield low-confidence or incorrect classification

## 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 the predicted label from the provided candidate list along with a confidence score indicating how strongly the text matches that category. The response typically includes the top label and may include ranked scores for all candidates.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "maxLength": 8000,
   "minLength": 1
  },
  "labels": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "maxItems": 20,
   "minItems": 2
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-intent-classification-d2c13cea/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)