# Crypto Fear & Greed Index API

> Crypto Fear & Greed Index API is a paid API for AI agents from api.strale.io, paid per call via x402, $0.0216/call, status unknown (last checked 2026-09-13).

Returns the current Crypto Fear & Greed Index value (0–100), its sentiment classification, and optional historical data for up to 30 days.

## Facts

- Endpoint: GET https://api.strale.io/x402/fear-greed-index
- Price: $0.0216/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-strale-io-45237cf6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_57nEfzUa57yjmLeJ_awpJ

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 api-strale-io-45237cf6
```

Example prompt: What's the current Crypto Fear & Greed Index, and can you also show me how sentiment has shifted over the last 14 days?

## When to prefer this

Use this endpoint when you need a simple, aggregated crypto market sentiment score without building your own index. Ideal for agents that need to factor in market mood for trading decisions, reports, or alerts. Prefer over raw on-chain data when a human-readable sentiment classification is needed quickly.

## Known failure modes

- Invalid 'days' parameter outside 1–30 range returns an error
- Upstream Alternative.me data unavailability may cause a 502 or empty response
- Network timeouts if the upstream provider is slow
- Payment failure (x402) if USDC balance is insufficient

## How this service works

Get the Crypto Fear & Greed Index — a market sentiment indicator from 0 (Extreme Fear) to 100 (Extreme Greed). Includes current value, classification, and optional historical data up to 30 days. Powered by Alternative.me.

## Output

Returns the current Fear & Greed Index numeric value (0–100), its text classification (e.g. 'Extreme Fear', 'Fear', 'Neutral', 'Greed', 'Extreme Greed'), timestamp, and optionally a list of historical daily values up to 30 days back.

## Example request

```json
{
 "days": 14
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "days": {
   "type": "number",
   "description": "Number of days of history (1-30). Default: 1"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "trend": {
  "type": "string"
 },
 "average": {
  "type": "number"
 },
 "history": {
  "type": "array"
 },
 "timestamp": {
  "type": "string"
 },
 "current_value": {
  "type": "number"
 },
 "classification": {
  "type": "string"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-strale-io-45237cf6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.strale.io](https://www.zero.xyz/host/api.strale.io/llms.txt)