# HERGERT SYNTHORA Fear & Greed Index

> HERGERT SYNTHORA Fear & Greed Index is a paid API for AI agents from api.hergertsynthora.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Returns the current crypto Fear & Greed Index from alternative.me, including today's value, the delta versus yesterday, and a band-crossing signal.

## Facts

- Endpoint: POST https://api.hergertsynthora.com/v1/fear-greed
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/hergert-synthora-fear-greed-index-2f66df24
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZPOFXsgdolVEe6CPi-oDV

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 hergert-synthora-fear-greed-index-2f66df24 -d '<json body>'
```

Example prompt: What's the crypto Fear & Greed Index right now, including how much it changed since yesterday and whether it crossed any band threshold — I want the dated, hash-verified reading from SYNTHORA?

## When to prefer this

Choose this endpoint when you need a verifiable, dated, and hash-stamped Fear & Greed Index reading that includes not just the raw value but also the day-over-day delta and a band-crossing signal — useful for trading agents needing auditable sentiment data rather than a bare index number from a generic source.

## Known failure modes

- Upstream alternative.me data unavailable — result may be stale or empty
- Malformed input string causes request rejection
- Payment not processed — x402 receipt missing, request not fulfilled
- Rate limit or infrastructure downtime returning 5xx errors
- Data hash mismatch indicating data integrity issue

## How this service works

SYNTHORA fear-greed: indice de miedo/codicia con la VARIACION frente a ayer y el cruce de banda, no solo el valor. Fuente: alternative.me, fechada y con hash.

## Output

A JSON object with ok:true, the niche identifier 'fear_greed', a result object containing the current Fear & Greed index value, the day-over-day change delta, a band-crossing indicator, a timestamp, and a data hash for verification, plus a payment receipt object confirming the x402 microtransaction.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "string",
   "description": "SYNTHORA fear-greed: indice de miedo/codicia con la VARIACION frente a ayer y el cruce de banda, no solo el valor. Fuente: alternative.me, fechada y con hash."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/hergert-synthora-fear-greed-index-2f66df24/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.hergertsynthora.com](https://www.zero.xyz/host/api.hergertsynthora.com/llms.txt)