Plans
Token and concurrency allowances are subject to change, so read the live values from the API (below) rather than hard-coding the numbers in your integration.
Token usage
Tokens are consumed by the model as your agents run, and they accrue against your plan’s per-period allowance. When the allowance runs out, creating a session (or messaging a finished one, which restarts it) fails with402 Payment Required. The error’s detail carries your limit, used, and the window_end when the budget resets. See Errors.
Check your current token usage with GET /api/v2/quota/tokens:
Response
Concurrent sessions
Separately from tokens, your plan caps how many sessions can run at once. A session holds a slot from the moment it leavesqueued until it reaches a terminal state, including when you cancel it. Queued sessions hold no slot.
GET /api/v2/sessions/quota returns your current concurrency usage:
Response
queue: false to get a 429 Too Many Requests instead.