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

# LiteLLM guardrails

> Add Silmaril as a LiteLLM pre-call and post-call guardrail and validate coverage in warn mode.

## Prerequisites

* A LiteLLM proxy that already routes model traffic.
* A Silmaril guardrail endpoint and API key from [deployment access](/docs/start/quickstart#get-access).
* If you [self-host](/docs/deployment/self-hosting), use the guardrail endpoint from the same deployment as your classify endpoint.

Set `SILMARIL_GUARDRAIL_URL` and `SILMARIL_API_KEY` in the proxy environment.

## Configure the guardrail

Start in warn mode while validating proxy coverage.

```yaml theme={"theme":"github-light-default"}
guardrails:
  - guardrail_name: silmaril-firewall
    litellm_params:
      guardrail: generic_guardrail_api
      mode: [pre_call, post_call]
      api_base: os.environ/SILMARIL_GUARDRAIL_URL
      headers:
        x-api-key: os.environ/SILMARIL_API_KEY
      default_on: true
      unreachable_fallback: fail_open
      additional_provider_specific_params:
        on_error: warn
```

This configuration applies the guardrail by default. An enforcement configuration is not included here. Agree on one with Silmaril before enabling blocking.

## Expected result

LiteLLM calls Silmaril before and after the model call. Would-block traffic returns warning metadata while the proxy call continues. If the guardrail cannot be reached, `unreachable_fallback: fail_open` also allows the call to continue.

## References

* [LiteLLM AI Gateway](https://docs.litellm.ai/docs/proxy/quick_start)
* [LiteLLM Guardrails Quick Start](https://docs.litellm.ai/docs/proxy/guardrails/quick_start)
* [LiteLLM Generic Guardrail API](https://docs.litellm.ai/docs/adding_provider/generic_guardrail_api)