Read your limits and usage
tenant.usage.self answers your app's exact usage next to each limit (storage bytes, documents, requests per minute, and the function limits: CPU, memory, concurrency, timeout, body and value sizes), with null for any limit not set.
{"name": "substrio_tenant_usage_self", "arguments": {}}tenant.limits reads your app's quota, document and request limits next to their live usage; account.usage reads an account's plan and usage counters across every app it has a plan or usage at.
curl -s $SUBSTRIO_URL/v1/_usage -H "Authorization: Bearer $SUBSTRIO_KEY"Check usage before a batch import or a traffic spike, not after a request starts failing.
Function limits: CPU, heap and wall time
Every function call runs under these bounds unless your app has its own limit set:
| Limit | Default | Over it |
|---|---|---|
| CPU time | 5,000 ms per call | 408 CF_CPU_TIMEOUT |
| JS heap | 256 MB per isolate | 413 CF_MEMORY_EXCEEDED |
| Wall clock | 30 s waiting on fetch and timers | the call fails naming the limit |
| Concurrency | 512 calls of the app at once | 429 over it |
Keep a function inside these by paging large reads, avoiding unbounded loops over external data, and setting a request timeout shorter than the wall-clock limit so your own code raises the error rather than the server. See function-errors and errors-and-retries for what a limit failure looks like on the wire.
Rate limits and 429s
A key's own requests_per_minute or request_budget (set when the key is created, or with account.key.update / tenant.key.update) answers 429 with Retry-After once spent; a request_budget never refills; raise it or rotate the key. Add your own rules with rate_limit.set (at most max_requests per window_seconds, counted per ip, token or tenant) for traffic you want bounded beyond the app-wide limit.
{"name": "substrio_rate_limit_set", "arguments": {"path": "/orders", "method": "POST", "by": "ip", "max_requests": 60, "window_seconds": 60}}Always read Retry-After and wait that long before retrying; see errors-and-retries for backoff.
Storage quotas and 507s
A write over the app's storage_bytes_limit or documents_limit answers 507 and stores nothing. Check tenant.usage.self against these limits (tenant.limits reads them) before a bulk write. Raise them by moving the account to a larger plan (account.plan.checkout returns the page to pay for one); a retry fails the same way until the limit changes.