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

# Degradation Modes

> How MemoryOS behaves when quotas or dependencies force partial service.

MemoryOS exposes its current operating mode on every response so your app keeps running regardless of what's happening with memory.

## Modes

| Mode                | Meaning                                                             |
| ------------------- | ------------------------------------------------------------------- |
| `FULL`              | Normal — reads and writes work as expected                          |
| `PASSTHROUGH`       | Memory context should be skipped — continue the LLM call without it |
| `DEGRADED_RETRIEVE` | Retrieval is reduced — fewer or zero memories may return            |
| `BLOCKED`           | Writes are blocked by quota governance                              |

## Response headers

| Header                        | Meaning                          |
| ----------------------------- | -------------------------------- |
| `X-MemoryOS-Quota-Mode`       | Current mode                     |
| `X-MemoryOS-Budget-Remaining` | Remaining budget as a percentage |
| `X-MemoryOS-Quota-Reset`      | Next reset timestamp             |
| `X-MemoryOS-Circuit-Status`   | Overall dependency health        |
| `X-MemoryOS-Processing`       | `normal` or `delayed`            |

## Handling passthrough

```python theme={null}
result = client.get(
    query=user_message,
    external_user_id="customer-123",
)

prompt_addition = "" if result.is_passthrough else result.system_prompt_addition
```

The rule is simple: **always make the LLM call**. Only skip MemoryOS context when passthrough is active.

## Webhooks

Operational events include `quota.warning`, `quota.critical`, `quota.exhausted`, `quota.reset`, `mode.changed`, `processing.delayed`, and `processing.recovered`.

See [Webhooks](/guides/webhooks) for payload format and signature verification.