diff --git a/README.md b/README.md
index b67920f..9205401 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,14 @@ Claude Code plugin marketplace by KeeperHub.
 
 ## Setup
 
+> **Prerequisite:** Claude Code's `/plugin marketplace add` clones this repository over SSH.
+> You need a GitHub SSH key configured before running the commands below.
+> If you see `Permission denied (publickey)`, see [GitHub's SSH setup guide](https://docs.github.com/en/authentication/connecting-to-github-with-ssh).
+> Alternatively, configure the MCP server directly without the plugin system:
+> ```
+> claude mcp add --transport http --scope user keeperhub https://app.keeperhub.com/mcp
+> ```
+
 ```
 /plugin marketplace add KeeperHub/claude-plugins
 /plugin install keeperhub@keeperhub-plugins