> ## Documentation Index > Fetch the complete documentation index at: https://docs.duraton.ai/llms.txt > Use this file to discover all available pages before exploring further. # Limits & defaults > Know the number before you hit it: every default and ceiling Duraton applies to pagination, request size, retries, AI steps, and connections. A reference for the numbers Duraton applies when you don't set one. Where a value is configurable, the option is linked. ## Requests & pagination | Limit | Value | Notes | | ---------------------- | ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Request body size | 1 MiB | Applies to every JSON request body and inbound webhook payload. Larger bodies are rejected. | | Cursor page size | `30` default, `200` max | `GET /runs`, `GET /webhook-deliveries`, and `GET /webhook-source-deliveries`. Set `limit` to change it; over `200` is clamped to `200`. | | Log & list page size | `100` default, `1000` max | `GET /events`, `/approvals`, `/control-actions`, and a run's `logs`. Over `1000` is clamped to `1000`. | | Session page size | `100` default, `500` max | `GET /sessions`. Over `500` is clamped to `500`. | | Unpaged reads | whole list | A run's `steps` take no `limit` - they return every row for that run. | | Pagination cursor | `X-Next-Cursor` header | `GET /runs`, `/webhook-deliveries`, and `/webhook-source-deliveries` use [keyset pagination](/reference/api/runs#keyset-pagination); pass the returned cursor to fetch the next page. | | Event name / id length | 256 characters | Applies to `name`, `app`, `runner`, `targetApp`, `dedupeId`, and `session` on `POST /events`. Over the bound returns `400`. | ## API rate limits Duraton does **not** impose a fixed per-second request rate limit on the API. There is no requests/second quota on `POST /events` or on the read endpoints, and no `429 Too Many Requests` / `Retry-After` back-off protocol to code against - a well-formed request is admitted regardless of how many preceded it. Two real ceilings apply instead: | Ceiling | Effect | | ------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Request body size (1 MiB) | A larger JSON body or inbound webhook payload is rejected outright (see above). | | Usage / plan limit | When a workspace reaches its plan's metered ceiling the project is **suspended**, and subsequent run-starting calls are refused with [`403 Forbidden`](/reference/api/errors) rather than throttled. | Suspension is the ceiling that actually gates throughput, and it is not a rate limit - it is a hard stop until usage falls back under the plan or the plan is raised. Its shape differs by endpoint: * **`POST /events` on a suspended project** still returns `202 Accepted`, but starts no new run: the response carries `suspended: true` with no `runId`, and any in-flight `waitForEvent` waiters are still woken. The event is recorded; only the fan-out into new runs is withheld. * Other run-creating actions (and cron-triggered runs) on a suspended project are refused with `403 Forbidden`. Because there is no request-rate throttle, protect a busy ingest path with your own client-side batching or concurrency limit; the durable back-pressure you *can* configure is per-workflow [flow control](/core/flow-control) (concurrency, throttle, rate-limit, debounce, batch), which shapes how fast admitted events turn into runs. ## Retries & delivery | Limit | Value | Configurable | | ------------------------- | ---------------------------------- | ----------------------------------------------------------------------------------------------------------------------- | | Step retries | none by default (`maxAttempts: 1`) | Per workflow via [`retry`](/core/retries). A failed step waits a backoff delay, then retries up to `maxAttempts` total. | | Outbound webhook attempts | up to `5` | Duraton retries a [failed delivery](/integrations/webhooks) with a backoff between attempts, then marks it `exhausted`. | | Outbound webhook timeout | `10s` per attempt | A slower endpoint counts as a failed attempt. | | Webhook signing | HMAC-SHA256 | The `X-Duraton-Signature` header on every inbound and outbound delivery. | ## AI steps | Default | Value | Option | | --------------------------- | ------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Provider | `anthropic` | [`provider`](/reference/sdk/ai-steps) on `step.ai.generate`. | | Re-asks on invalid output | `1` | [`reask`](/reference/sdk/ai-steps); applies only when an `output` schema is set. | | Inference cache TTL | 24 hours | [`cache`](/reference/sdk/ai-steps) - pass `{ ttlMs }` to change it. | | Inference cache eligibility | `temperature` set and `<= 0.2` | The cache is a no-op when `temperature` is above `0.2` **or** left unset (a provider default is often non-deterministic), so only near-deterministic calls are reused. | | Embedding batch size | `100` inputs per durable batch | [`batchSize`](/reference/sdk/ai-steps) on `step.ai.embed`. | Per-run AI spend ceilings are opt-in and unlimited by default - see [`cap`](/ai/cost-controls). ## Connection defaults These are what the SDK uses when a value and its environment variable are both unset: | Setting | Default | Environment variable | | ------------------------- | -------------------------------- | ------------------------------------------------------------------------------------------------------------- | | `url` | `https://run.duraton.dev` | `DURATON_URL` | | `apiKey` | none - required on every request | `DURATON_API_KEY` | | App | `default` | `DURATON_APP` | | Runner heartbeat interval | `30s` | - (a [`connect`](/reference/sdk/connect) endpoint is refreshed on its socket heartbeat) | | Runner liveness TTL | `90s` since the last heartbeat | - (a runner past it shows as **Stale** and is listed with `live: false`) | | Protocol version | `1` | - (checked in the Connect handshake; see the [protocol reference](/reference/wire-protocol#protocol-version)) |