# fastapi.online Hashtag Generator

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

Generates a specified number of relevant hashtags for a given piece of content using self-hosted AI inference

## Facts

- Endpoint: POST https://api.fastapi.online/hashtag-generate
- Price: $0.001/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-hashtag-generator-2715d39b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tfVB7KhoEKaKxbzl1zeVa

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-hashtag-generator-2715d39b -d '<json body>'
```

Example prompt: Generate 10 hashtags for this Instagram post: 'Just launched our new line of sustainable bamboo water bottles — eco-friendly, durable, and perfect for outdoor adventures. Available now on our website!'

## When to prefer this

Choose this endpoint when you need quick, AI-generated hashtag suggestions for social media posts, blog content, or marketing copy at very low cost ($0.001/call) with no signup required. It's ideal for agents automating content pipelines or social media scheduling where hashtag enrichment is a lightweight step. Prefer it over manual hashtag research tools when volume is high and per-call cost sensitivity is low.

## Known failure modes

- Content too short or empty — minLength:1 enforced, blank input rejected
- Count out of range — must be between 1 and 30, otherwise validation error
- Content too long — maxLength:8000 characters enforced
- Payment failure — x402 payment not provided or insufficient USDC balance
- Model inference timeout — self-hosted model may occasionally be slow or unavailable
- Generic or ambiguous content may produce low-quality or irrelevant hashtags

## 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

A list of relevant hashtags (up to 30) tailored to the provided content, returned as an array or structured text ready to paste into a social media post.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "count": {
   "type": "integer",
   "maximum": 30,
   "minimum": 1
  },
  "content": {
   "type": "string",
   "maxLength": 8000,
   "minLength": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-hashtag-generator-2715d39b/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)