Service index

curl -s "https://api.beliefsystems.xyz/v1" \
  -H "Authorization: Bearer $BELIEF_API_KEY"

import os
import requests

resp = requests.get(
    "https://api.beliefsystems.xyz/v1",
    headers={"Authorization": f"Bearer {os.environ['BELIEF_API_KEY']}"},
    timeout=10,
)
resp.raise_for_status()

payload = resp.json()
print(payload["data"])

const res = await fetch("https://api.beliefsystems.xyz/v1", {
  headers: { Authorization: `Bearer ${process.env.BELIEF_API_KEY}` },
});
if (!res.ok) throw new Error(`Belief Systems API ${res.status}`);

const { data, meta } = await res.json();
console.log(data);

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.beliefsystems.xyz/v1",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.beliefsystems.xyz/v1"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.get("https://api.beliefsystems.xyz/v1")
  .header("Authorization", "Bearer <token>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.beliefsystems.xyz/v1")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'

response = http.request(request)
puts response.read_body

{
  "data": {
    "docsUrl": "https://docs.beliefsystems.xyz/api-reference/introduction",
    "endpoints": [
      {
        "description": "Service index: endpoints, limits, and your remaining quota",
        "path": "/v1"
      },
      {
        "description": "The published index catalog with staleness labels",
        "path": "/v1/indices"
      },
      {
        "description": "Current level, not delayed",
        "path": "/v1/indices/{ticker}/latest"
      },
      {
        "description": "Level history at 1h or 1d",
        "path": "/v1/indices/{ticker}/history"
      },
      {
        "description": "Completed composition changes",
        "path": "/v1/indices/{ticker}/reconstitutions"
      },
      {
        "description": "The Belief Volatility catalog",
        "path": "/v1/volatility"
      },
      {
        "description": "Latest published volatility reading",
        "path": "/v1/volatility/{ticker}/latest"
      },
      {
        "description": "Volatility history",
        "path": "/v1/volatility/{ticker}/history"
      },
      {
        "description": "Pointers to the free point-in-time snapshots",
        "path": "/v1/downloads"
      }
    ],
    "key": {
      "limitDay": 2000,
      "limitMinute": 60,
      "prefix": "belief_live_a1b2c3d4",
      "remainingDay": 1873,
      "remainingMinute": 59
    },
    "limits": {
      "historyMaxDays": 90,
      "intervals": [
        "1h",
        "1d"
      ],
      "requestsPerDay": 2000,
      "requestsPerMinute": 60
    },
    "version": "v1"
  },
  "meta": {
    "attribution": "Source: Belief Systems (beliefsystems.xyz)",
    "generatedAt": "2026-08-31T14:01:22.277647Z",
    "license": "https://beliefsystems.xyz/license",
    "termsUrl": "https://beliefsystems.xyz/terms"
  }
}

{
  "error": {
    "code": "invalid_api_key",
    "docsUrl": "https://docs.beliefsystems.xyz/api-reference/limits#invalid-api-key",
    "message": "This endpoint requires a Data API key. Create one free at https://beliefsystems.xyz/data ; programmatic or commercial licensing is at https://beliefsystems.xyz/license.",
    "requestId": "9f2c1ad4e6b74c0f8a3d5e1b7c904a26"
  }
}

{
  "error": {
    "code": "rate_limited",
    "docsUrl": "https://docs.beliefsystems.xyz/api-reference/limits#rate-limited",
    "message": "Rate limit exceeded: 60 requests per minute per key.",
    "requestId": "9f2c1ad4e6b74c0f8a3d5e1b7c904a26"
  }
}

{
  "error": {
    "code": "invalid_api_key",
    "docsUrl": "<string>",
    "message": "<string>",
    "requestId": "<string>"
  }
}