Authentication

All API requests require a Bearer token in the Authorization header.

Making authenticated requests

Authorization: Bearer thd_aBcDeFgHiJkLmNoPqRsTuVwX

API keys follow the format thd_ followed by 24 alphanumeric characters. Generate keys from your API Keys dashboard.

Product-based access

Your API key grants access based on your subscription. Each product is a separate plan with its own API key.

Advanced Chart API

Covers all chart generation, astrology, and transit endpoints:

/api/chart, /api/composite, /api/astrology, /api/transits/*, /api/retrogrades, /api/returns, /api/multi-chart

Available via Whop (3-month or annual) or Nas.io (lifetime).

SAGE API — Separate Plan

AI-powered knowledge engine and MCP server access:

/api/sage, /mcp

SAGE API is a separate subscription from Advanced Chart — it requires its own API key. An Advanced Chart key cannot access SAGE or MCP endpoints. Contact us to subscribe.

You can hold both keys simultaneously. Each key's rate limits and unit consumption are tracked independently.

Key management

You can create up to 10 API keys per account
Keys are shown only once at creation — store them securely
Revoke compromised keys immediately from your dashboard
Each key inherits the products from your current subscription

Error responses

If your key is missing, invalid, or lacks access to the requested endpoint:

Status	Error	Cause
`401`	`Missing API key`	No `Authorization` header provided
`401`	`Invalid API key`	Key not found or malformed
`403`	`No active subscription`	Key belongs to an expired or cancelled plan
`403`	`Product not available`	Your plan doesn't include the required product

See the full Error Codes reference for all possible error responses.