> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fact0.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Rate limits

> Ingest rate limiting and retry behavior.

# Rate limits

Rate limiting applies to **audit ingest** and **telemetry ingest** routes when enabled in server configuration.

## HTTP 429

When rate limited, the API returns `429 Too Many Requests` with a `Retry-After` header (seconds).

The SDK automatically retries on 429 and 5xx with exponential backoff (default 3 attempts).

## SDK retry policy

| Status             | Behavior                                  |
| ------------------ | ----------------------------------------- |
| 429                | Retry with backoff; respect `Retry-After` |
| 500, 502, 503, 504 | Retry with backoff                        |
| 400, 401, 403, 409 | Fail immediately                          |

## Batching defaults

| Setting             | Default     |
| ------------------- | ----------- |
| `batch_max_size`    | 100 events  |
| `batch_max_wait_ms` | 500 ms      |
| Max batch on wire   | 1000 events |

Batching reduces request volume and helps stay under rate limits.

## Metrics

The platform exposes `fact0_ratelimit_dropped_total` on `/metrics` for observability.