> ## Documentation Index
> Fetch the complete documentation index at: https://docs.beliefsystems.xyz/llms.txt
> Use this file to discover all available pages before exploring further.
# Your first request
> Mint a key, read a Belief index level, and chart the trailing window – in curl, Python, or JavaScript.
Create an account and mint a key at [beliefsystems.xyz/data](https://beliefsystems.xyz/data/signup?source=docs-quickstart). Free, work email, no password, about a minute.
The secret is shown once. Put it in your environment:
```bash theme={null}
export BELIEF_API_KEY="belief_live_..."
```
`GET /v1` is the cheapest way to confirm a key works. It answers with every endpoint, the free-tier limits, and your own remaining quota.
```bash theme={null}
curl -s https://api.beliefsystems.xyz/v1 \
-H "Authorization: Bearer $BELIEF_API_KEY"
```
```json theme={null}
{
"data": {
"version": "v1",
"limits": {
"requestsPerMinute": 60,
"requestsPerDay": 2000,
"historyMaxDays": 90,
"intervals": ["1h", "1d"]
},
"key": {
"prefix": "belief_live_a1b2c3d4",
"limitMinute": 60,
"limitDay": 2000,
"remainingMinute": 59,
"remainingDay": 1873
}
}
}
```
A `401` here means the key is wrong, not that the endpoint is. Check [`invalid_api_key`](/api-reference/limits#invalid-api-key).
`CONFLICT` is the Belief Global Conflict Risk Escalation Expectations Index. `GET /v1/indices` lists every published ticker.
```bash curl theme={null}
curl -s https://api.beliefsystems.xyz/v1/indices/CONFLICT/latest \
-H "Authorization: Bearer $BELIEF_API_KEY"
```
```python Python theme={null}
import os
import requests
resp = requests.get(
"https://api.beliefsystems.xyz/v1/indices/CONFLICT/latest",
headers={"Authorization": f"Bearer {os.environ['BELIEF_API_KEY']}"},
timeout=10,
)
resp.raise_for_status()
latest = resp.json()["data"]
print(latest["ticker"], latest["indexLevel"], latest["computedAt"])
```
```javascript JavaScript theme={null}
const res = await fetch("https://api.beliefsystems.xyz/v1/indices/CONFLICT/latest", {
headers: { Authorization: `Bearer ${process.env.BELIEF_API_KEY}` },
});
if (!res.ok) throw new Error(`Belief Systems API ${res.status}`);
const { data } = await res.json();
console.log(data.ticker, data.indexLevel, data.computedAt);
```
```json theme={null}
{
"data": {
"ticker": "CONFLICT",
"name": "Belief Global Conflict Risk Escalation Expectations Index",
"computedAt": "2026-08-31T13:44:44.963697Z",
"indexLevel": "36.11697608",
"baseIndexLevel": "100.00000000",
"stale": false,
"publicStatus": "active",
"maturityType": "PERPETUAL",
"methodologyVersion": "midprice-v1",
"dataQuality": {
"freshMarketsCount": 24,
"staleMarketsCount": 0,
"totalMarketsCount": 24,
"freshDataPct": 100.0
}
},
"meta": {
"attribution": "Source: Belief Systems (beliefsystems.xyz)",
"generatedAt": "2026-08-31T14:01:28.178537Z"
}
}
```
Every index is based at 100 on its inception date, so a level reads on its own: `CONFLICT` at 36.12 is down 63.9% since inception.
`indexLevel` is a decimal **string**, not a number. Parse it with a decimal type – see [Conventions](/api-reference/conventions#levels-are-decimal-strings).
History reaches back 90 days, at `1h` or `1d`. With no parameters you get the full window at `1d`.
```bash curl theme={null}
curl -s "https://api.beliefsystems.xyz/v1/indices/CONFLICT/history?interval=1d" \
-H "Authorization: Bearer $BELIEF_API_KEY"
```
```python Python theme={null}
import os
from decimal import Decimal
import requests
resp = requests.get(
"https://api.beliefsystems.xyz/v1/indices/CONFLICT/history",
params={"interval": "1d"},
headers={"Authorization": f"Bearer {os.environ['BELIEF_API_KEY']}"},
timeout=10,
)
resp.raise_for_status()
payload = resp.json()
points = payload["data"]["points"]
first, last = Decimal(points[0]["indexLevel"]), Decimal(points[-1]["indexLevel"])
change = (last / first - 1) * 100
# Label the chart with what you were served, not what you asked for.
window = payload["meta"]
print(f"{window['effectiveStart']} to {window['effectiveEnd']}: {change:+.2f}%")
```
```javascript JavaScript theme={null}
const url = new URL("https://api.beliefsystems.xyz/v1/indices/CONFLICT/history");
url.searchParams.set("interval", "1d");
const res = await fetch(url, {
headers: { Authorization: `Bearer ${process.env.BELIEF_API_KEY}` },
});
if (!res.ok) throw new Error(`Belief Systems API ${res.status}`);
const { data, meta } = await res.json();
const first = Number(data.points.at(0).indexLevel);
const last = Number(data.points.at(-1).indexLevel);
// Label the chart with what you were served, not what you asked for.
console.log(meta.effectiveStart, meta.effectiveEnd, `${((last / first - 1) * 100).toFixed(2)}%`);
```
A `start` older than 90 days is clamped, not rejected, so a chart that asked for a year still renders. `meta.clamped` tells you it happened and `meta.effectiveStart` tells you where the data really begins. Read them before labeling an axis.
## Where to go next
Decimal strings, timestamps, staleness, and clamping – the four things that surprise people.
60 per minute, 2,000 per day, and how to back off correctly.
What the volatility series measure and how to quote one.
Full history since inception, composition, and weights, as free CSVs.
## Common first errors
| What you see | What it means |
| ------------------------- | -------------------------------------------------------------------------------------------------------------------- |
| `401 invalid_api_key` | No key, a typo, or a key that was rotated or revoked |
| `404 not_found` | The ticker is not on this surface. `GET /v1/indices` is the catalog |
| `422 invalid_interval` | `interval` must be `1h` or `1d` |
| `429 rate_limited` | Sleep for `Retry-After` seconds, which is exact |
| CORS failure in a browser | Expected. This API is server-to-server – see [Authentication](/api-reference/authentication#keys-belong-on-a-server) |