Universe API

Endpoint

GET /v1/universe

No authentication required Rate Limited: Yes

Parameters

Name	In	Required	Default	Description
`sort`	query	no	tier	`tier` (tier-1 first, then tier-2; curator order preserved within each) or `symbol` (alphabetical).
`limit`	query	no	200	Clamped to [1, 1000].

curl "https://lab.flashalpha.com/v1/universe?sort=symbol&limit=20"

import requests

resp = requests.get(
    "https://lab.flashalpha.com/v1/universe",
    params={"sort": "symbol", "limit": 20}
)
data = resp.json()
print(f"Universe size: {data['count']}")

const resp = await fetch(
  "https://lab.flashalpha.com/v1/universe?sort=symbol&limit=20"
);
const data = await resp.json();
console.log("Universe size: " + data.count);

API Key

Response

{
  "as_of": "2026-05-30T15:30:00Z",
  "count": 252,
  "returned": 20,
  "limit": 20,
  "sort": "symbol",
  "symbols": [
    { "symbol": "AAPL", "tier": 1, "is_pre_warmed": true },
    { "symbol": "AMD",  "tier": 1, "is_pre_warmed": true }
  ]
}

Key Response Fields

Field	Description
`count`	Total universe size (tier-1 ∪ tier-2, deduplicated).
`returned`	`min(count, limit)`.
`sort`	Echoes the effective sort (unknown values fall back to `tier`).
`symbols[].tier`	1 = high-traffic loop (fast refresh); 2 = remaining curated symbols.
`symbols[].is_pre_warmed`	Currently always `true` - the screener loop keeps every universe member populated.

Errors

Status	Description
`200`	Public endpoint - returns the universe directory; no auth-related errors.

About

Universe returns the curated tier-1 and tier-2 symbol directory the screener background loop keeps pre-warmed in MarketDataStore. It is public with no auth required, so retail evaluators can introspect coverage before subscribing. Tier-1 symbols sit on the high-traffic fast-refresh loop; tier-2 covers the remaining curated set.

Symbols outside the universe still work on any authenticated endpoint - they fetch on-demand - so the universe is "guaranteed warm," not "exhaustive." On the Free tier, requests for off-universe symbols return 403 symbol_not_in_free_universe, and this endpoint lets evaluators see exactly which symbols are reachable on Free.

Common Use Cases

Inspect coverage before subscribing - read count to size the guaranteed-warm universe with no API key
Populate a symbol picker - iterate symbols[].symbol to seed a dropdown or autocomplete from the warm set
Scope free-tier access - cross-check candidate tickers against the list to avoid 403 symbol_not_in_free_universe on Starter
Prioritize fast-refresh names - filter on symbols[].tier == 1 to poll high-traffic symbols more aggressively
Confirm pre-warm status - check symbols[].is_pre_warmed before assuming a symbol returns instantly rather than fetching on-demand
Detect universe drift - diff symbols[] across days, keyed on as_of, to catch curator additions and removals
Page large pulls - set sort=symbol and walk limit (clamped to 1000) to retrieve the full directory deterministically

Complementary endpoints

Screener - rank and filter the universe by IV, flow, and exposure metrics
Exposure Basket - aggregate dealer positioning across a chosen list of universe symbols
API Reference - full endpoint catalog to act on the symbols you discover here