# fastapi.online — Webhook Handler Generator

> fastapi.online — Webhook Handler Generator is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.005/call, status down (last checked 2026-10-21).

Generates webhook handler code for a specified service and set of events

## Facts

- Endpoint: POST https://api.fastapi.online/generate-webhook-handler?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: down
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastapi-online-webhook-handler-generator-f6029a95
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_JU7N8LHUHICW8jIzLHT8o

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-webhook-handler-generator-f6029a95 -d '<json body>'
```

Example prompt: Generate a webhook handler for Stripe that handles the payment_intent.succeeded and customer.subscription.deleted events.

## When to prefer this

Choose this endpoint when you need quick, pay-per-call webhook handler scaffolding without signing up for a full code-generation platform. Ideal for agents automating developer workflows or helping users bootstrap integrations with common services like Stripe, GitHub, or Shopify.

## Known failure modes

- Unknown or unsupported service name may produce generic or low-quality code
- Overly broad or vague event strings may yield incomplete handlers
- Missing required 'service' field returns a validation error
- Very long events strings exceeding maxLength are rejected

## 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 generated source code for a webhook handler that processes the specified events from the given service, ready to integrate into a backend application.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "events": {
   "type": "string",
   "maxLength": 300,
   "description": "events to handle"
  },
  "service": {
   "type": "string",
   "maxLength": 2000,
   "minLength": 2,
   "description": "the service sending webhooks (e.g. Stripe, GitHub)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-webhook-handler-generator-f6029a95/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)