x402 Agent Services Fear Greed Index API
The Fear Greed Index API from x402 Agent Services — 1 operation(s) for fear greed index.
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curl "https://apis.io/api/v1/apis/call402-com:call402-com-fear-greed-index-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: x402 Agent Services Fear Greed Index API
version: 1.0.0
contact:
name: x402 Agent Services
url: https://call402.com/
x-guidance: 'All /api/* endpoints are pay-per-call via x402 v2 (exact, Base mainnet, USDC). Call any endpoint without payment to receive the live 402 challenge with exact price, network, asset and payTo; the runtime 402 response is authoritative over this document. Pay with any x402 client (e.g. @x402/fetch) and retry with the PAYMENT-SIGNATURE header. Free endpoints: /, /pricing, /stats, /health, /openapi.json, /llms.txt, /.well-known/x402.json, /.well-known/agent.json, and POST /mcp for initialize/tools/list.'
description: USDC pay-per-call APIs for AI agents via the x402 protocol (v2, exact, Base mainnet). Send a request, receive HTTP 402 with payment requirements, pay with @x402/fetch or any x402 client, retry with the PAYMENT-SIGNATURE header.
servers:
- url: https://call402.com
tags:
- name: Fear Greed Index
paths:
/api/fear-greed-index:
post:
summary: Crypto fear and greed index
description: 'Crypto Fear & Greed Index by alternative.me: current value (0-100) and classification (Extreme Fear, Fear, Neutral, Greed, Extreme Greed) plus optional daily history. The most-cited single market-sentiment gauge for crypto trading agents: position sizing, risk checks and regime detection before trading. Data published by alternative.me for free commercial use with attribution; served from a 30-minute cache.'
operationId: Crypto_fear_and_greed_index
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.005'
protocols:
- x402: {}
network: eip155:8453
asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
payTo: '0xAc6F1C3C3b17040730F16dC24Ee9993e9565BE4A'
scheme: exact
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
limit:
type: integer
required: []
example:
limit: 1
responses:
'200':
description: Success (after x402 payment settles)
content:
application/json:
schema:
type: object
description: Tool result payload; per-endpoint fields are documented in the docs page and llms.txt
example:
value: 32
value_classification: Fear
timestamp: '2026-11-03'
source: alternative.me
'400':
description: Invalid input
'402':
description: Payment Required — x402 v2 challenge in PAYMENT-REQUIRED header
headers:
PAYMENT-REQUIRED:
schema:
type: string
description: Base64-encoded PaymentRequired JSON
tags:
- Fear Greed Index
x-x402:
version: 2
network: eip155:8453
asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
payTo: '0xAc6F1C3C3b17040730F16dC24Ee9993e9565BE4A'
facilitator: https://api.cdp.coinbase.com/platform/v2/x402