Update chat-completion.mdx

universal endpoint + openai compat bonus value

Author: kathayl

src/content/docs/ai-gateway/chat-completion.mdx

@@ -64,7 +64,7 @@ curl -X POST https://gateway.ai.cloudflare.com/v1/{account_id}/{gateway_id}/comp
 
 ### Universal provider
 
-You can also use this pattern with a [Universal Endpoint](/ai-gateway/universal/).
+You can also use this pattern with the [Universal Endpoint](/ai-gateway/universal/) to add [fallbacks](/ai-gateway/configuration/fallbacks/) across multiple providers. When used in combination, every response, no matter if it comes from the primary model or a fallback will return the same standardized format, so no extra parsing logic is required. 
 
 ```ts title="index.ts"
 export interface Env {