Update prompts-guide.mdx

docs/cody/prompts-guide.mdx

@@ -98,7 +98,7 @@ You can learn more about context [here](/cody/core-concepts/context).
 ### Indexing your repositories for context
 @-mention local and current repositories are only available if you have your repository indexed. Enterprise and Enterprise Starter users can request their admins to add their local project for indexing to get access to @-mention context. 
 
-Repository indexing is only available to [Tier 1 Code Hosts](https://sourcegraph.com/docs/admin/code_hosts), please reach out to your admins if you require assistance with indexing. 
+Repository indexing is only available to supported [Code Hosts](https://sourcegraph.com/docs/admin/code_hosts), please reach out to your admins if you require assistance with indexing. 
 
 
 ## Selecting the right LLM