# SperaxOS Fear & Greed Index API

> SperaxOS Fear & Greed Index API is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-20).

Returns the current crypto market Fear & Greed Index score and sentiment label, payable per-request via x402 USDC on Base

## Facts

- Endpoint: GET https://chat.sperax.io/api/x402/intel/fear-greed?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-fear-greed-index-api-74fa5ca8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OlMVDYaeTcAp571b4n1BE

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 speraxos-fear-greed-index-api-74fa5ca8
```

Example prompt: What's the current crypto fear and greed index score right now — is the market in fear or greed territory?

## When to prefer this

Prefer this endpoint when you need a real-time, pay-per-use crypto market sentiment signal without managing API keys. It is ideal for AI agents operating with on-chain USDC wallets on Base that need to integrate market mood into DeFi decisions, trading strategies, or portfolio monitoring workflows. Use it over free alternatives when freshness and programmable micropayment access are priorities.

## Known failure modes

- Payment not included or insufficient USDC — returns 402 Payment Required
- Base network congestion causing payment verification delay — timeout or retry needed
- Index data temporarily unavailable from upstream provider — may return 503 or stale data
- Malformed x402 payment header — returns 400 Bad Request

## How this service works

AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.

## Output

Returns the current Fear & Greed Index numeric score (typically 0–100) and a sentiment label (e.g. Extreme Fear, Fear, Neutral, Greed, Extreme Greed), along with a timestamp indicating when the reading was recorded.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-fear-greed-index-api-74fa5ca8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.sperax.io](https://www.zero.xyz/host/chat.sperax.io/llms.txt)