Alterscope Developer API

The API enforces a per-minute rate limit (with a short burst allowance) and a per-month request quota, both keyed to your plan tier. The values below are the live plan limits.

Per-tier limits

	Free	Analyst	Team	Enterprise	Custom
Requests / minute	20	100	500	2,000	5,000
Burst	10	20	50	200	1,000
Requests / month	50,000	500,000	5,000,000	Unlimited	Unlimited
WebSocket connections	1	5	25	100	500
Signed webhooks	—	—	25	Unlimited	Unlimited
Risk-events WebSocket	No	Yes	Yes	Yes	Yes
Webhook replay window	—	1 day	7 days	30 days	90 days
Data retention	28 days	180 days	730 days	2,555 days	Unlimited

Custom plans are arranged directly with sales. Enterprise and Custom monthly request quotas are uncapped.

Rate-limit headers

Every authenticated response carries the current rate-limit state, not just 429s. Read these headers on successful responses to throttle proactively, before you ever hit the limit:

Header	Meaning
`X-RateLimit-Limit`	The token-bucket capacity the limit is measured against for your key.
`X-RateLimit-Remaining`	Tokens left in the current window after this request. When it reaches `0`, the next request may be rejected.
`X-RateLimit-Reset`	Unix timestamp (in seconds) when the window resets and tokens replenish.

The headers are set on success responses as well as on 429, so you can watch X-RateLimit-Remaining trend toward 0 and slow down before a request is rejected.

A simple proactive strategy: if X-RateLimit-Remaining is low, pause until the X-RateLimit-Reset timestamp before sending more requests rather than waiting for a 429.

When you exceed the per-minute limit

A request over the per-minute rate returns 429 Too Many Requests with the rate-limit headers above plus a Retry-After:

Retry-After: 60
X-RateLimit-Limit: <your bucket capacity>
X-RateLimit-Remaining: 0
X-RateLimit-Reset: <unix timestamp when the window resets>

Wait for the Retry-After interval (in seconds) before retrying, and prefer exponential backoff if you hit the limit repeatedly. The body follows the standard error envelope.

For write requests, retrying after a 429 is safe to do with an idempotency key (X-Idempotency-Key) — the same key replays the original result instead of performing the action twice.

Tips

Use the limit and pagination parameters to fetch only what you need.
Subscribe to WebSockets or webhooks for live data instead of polling.
If you consistently approach a limit, contact sales about a higher tier.

See Errors for the full status-code reference and Scopes for what your key can access.

​Per-tier limits

​Rate-limit headers

​When you exceed the per-minute limit

​Tips

Per-tier limits

Rate-limit headers

When you exceed the per-minute limit

Tips