diff --git a/README.md b/README.md
index bc14f80..911cc4b 100644
--- a/README.md
+++ b/README.md
@@ -25,7 +25,7 @@ Before you begin, ensure you have the following:
 * One of the supported agent harnesses, installed and authenticated:
   * [Gemini CLI](https://github.com/google-gemini/gemini-cli) (v0.6.0+)
   * [Claude Code](https://code.claude.com)
-  * [Codex](https://developers.openai.com/codex)
+  * [Codex](https://developers.openai.com/codex) (v0.150.0+)
   * [Antigravity CLI](https://antigravity.google)
 * [Node.js](https://nodejs.org/) (the MCP server runs via `npx`).
 * A running MySQL instance.
diff --git a/plugin.json b/plugin.json
index 0836555..17db01d 100644
--- a/plugin.json
+++ b/plugin.json
@@ -1,4 +1,5 @@
 {
+  "$schema": "https://agent-plugins.org/schemas/1.0.0/plugin.schema.json",
   "name": "mysql",
   "version": "0.1.6",
   "description": "Connect and interact with a MySQL database and data",