Authentication

The Skylit Public API uses bearer authentication. Send your API key in the Authorization header on every request:

Authorization: Bearer <your-api-key>

Getting a key

Generate and manage keys on the Developer page (API keys tab). New accounts start with the credits their plan includes (see Plans and credits); GET /v1/account shows the balance. MCP clients such as Claude, Claude Code and Cursor can also sign in with Skylit (OAuth) instead of using a key: see the MCP quickstart.

curl "https://api.skylit.ai/v1/heatmap?symbols=SPY" \
  -H "Authorization: Bearer $SKYLIT_API_KEY"

import os, requests

session = requests.Session()
session.headers["Authorization"] = f"Bearer {os.environ['SKYLIT_API_KEY']}"
print(session.get("https://api.skylit.ai/v1/heatmap", params={"symbols": "SPY"}).json())

const skylit = (path) =>
  fetch(`https://api.skylit.ai${path}`, {
    headers: { Authorization: `Bearer ${process.env.SKYLIT_API_KEY}` },
  }).then((r) => r.json());

console.log(await skylit("/v1/heatmap?symbols=SPY"));

Credits

Every chargeable request debits a fixed cost from your credit balance (1 credit = $0.001). Each endpoint's cost is shown on its API Reference page (x-credits in the OpenAPI specs). /v1/account and /v1/openapi.json are free. Streams charge to open and then per symbol per minute; the connected event states the rate.

Every chargeable response carries X-Credits-Remaining: <balance>. Failed calls are free: a request answered with any 4xx or 5xx is refunded, and its X-Credits-Remaining already reflects the refund.

Rate limits

Each key has a requests-per-minute limit set by your plan, shared across all Skylit APIs. GET /v1/account returns it (limits.requestsPerMinute) along with your other limits, so read it rather than hard-coding a number.

Every response carries the key's current window:

For backoff code and the full retry rules, see Rate limits and retries. Every error code is listed on Errors.