Fix current Codex plugin marketplace compatibility

.agents/plugins/marketplace.json

@@ -0,0 +1,20 @@
+{
+  "name": "21st",
+  "interface": {
+    "displayName": "21st.dev"
+  },
+  "plugins": [
+    {
+      "name": "21st",
+      "source": {
+        "source": "local",
+        "path": "./"
+      },
+      "policy": {
+        "installation": "AVAILABLE",
+        "authentication": "ON_INSTALL"
+      },
+      "category": "Developer Tools"
+    }
+  ]
+}

.codex-plugin/plugin.json

@@ -7,7 +7,23 @@
     "url": "https://21st.dev"
   },
   "homepage": "https://21st.dev",
+  "repository": "https://github.com/21st-dev/codex-plugin",
+  "license": "Apache-2.0",
   "keywords": ["react", "shadcn", "ui", "components", "mcp", "frontend", "cli"],
-  "skills": ["./skills"],
-  "mcp": "./.mcp.json"
+  "skills": "./skills/",
+  "mcpServers": "./.mcp.json",
+  "interface": {
+    "displayName": "21st.dev",
+    "shortDescription": "Search, install, and publish React/shadcn UI",
+    "longDescription": "Search, install, and publish React/shadcn components, themes, and templates on 21st.dev using bundled skills and the remote 21st MCP server.",
+    "developerName": "21st.dev",
+    "category": "Developer Tools",
+    "capabilities": ["Interactive", "Read", "Write"],
+    "websiteURL": "https://21st.dev",
+    "defaultPrompt": [
+      "Find a polished shadcn component for my current UI.",
+      "Install a 21st.dev component into this project.",
+      "Publish this component to 21st.dev."
+    ]
+  }
 }

.mcp.json

@@ -1,5 +1,5 @@
 {
-  "mcp_servers": {
+  "mcpServers": {
     "21st": {
       "url": "https://21st.dev/api/mcp",
       "bearer_token_env_var": "API_KEY_21ST"

README.md

@@ -38,6 +38,12 @@ instead of hand-writing UI.
    (Replace `21st-dev/codex-plugin` with the actual `<org>/<repo>`, git URL, or
    local path that hosts this directory.)
 
+   Refresh the Git-backed marketplace later with:
+
+   ```bash
+   codex plugin marketplace upgrade 21st
+   ```
+
 3. Open the in-CLI plugin browser and install `21st`:
 
    ```
@@ -68,7 +74,9 @@ the shell that launched Codex.
 .codex-plugin/
   plugin.json     # skills + mcp references
 .mcp.json         # remote 21st MCP (bearer via API_KEY_21ST env)
-marketplace.json  # self-hosted marketplace listing this plugin
+.agents/plugins/
+  marketplace.json  # Codex marketplace manifest
+marketplace.json    # legacy marketplace manifest
 skills/
   21st-cli-use/
     SKILL.md       # bundled skills (shared with the Claude Code plugin