Add default field to input schema and GITHUB_HOST to GitHub definition

- Add `default` property to input schema for optional default values
- Add GITHUB_HOST input to GitHub server definition with default "https://api.github.com"
- Pass GITHUB_HOST env var through Docker -e flag

https://claude.ai/code/session_013AxurW8hPAfnUNvik354Xx

Author: claude

schemas/server-definition.schema.json

@@ -223,6 +223,10 @@
           "type": "string",
           "description": "Help text for this input"
         },
+        "default": {
+          "type": "string",
+          "description": "Default value for this input. Used when the user does not provide a value."
+        },
         "placeholder": {
           "type": "string",
           "description": "Placeholder text"

servers/com.github-mcp.json

@@ -13,12 +13,14 @@
     "type": "stdio",
     "command": "docker",
     "args": [
-      "run", "-i", "--rm", "-e",
-      "GITHUB_PERSONAL_ACCESS_TOKEN",
+      "run", "-i", "--rm",
+      "-e", "GITHUB_PERSONAL_ACCESS_TOKEN",
+      "-e", "GITHUB_HOST",
       "ghcr.io/github/github-mcp-server"
     ],
     "env": {
-      "GITHUB_PERSONAL_ACCESS_TOKEN": "${input:GITHUB_PERSONAL_ACCESS_TOKEN}"
+      "GITHUB_PERSONAL_ACCESS_TOKEN": "${input:GITHUB_PERSONAL_ACCESS_TOKEN}",
+      "GITHUB_HOST": "${input:GITHUB_HOST}"
     },
     "metadata": {
       "inputs": [
@@ -35,6 +37,16 @@
             "instructions": "1. Click 'Generate new token (classic)'\n2. Give it a name like 'McpMux'\n3. Select scopes: repo, read:org\n4. Click 'Generate token'\n5. Copy the token (starts with ghp_)",
             "button_label": "Create Token"
           }
+        },
+        {
+          "id": "GITHUB_HOST",
+          "label": "GitHub Host",
+          "description": "GitHub hostname. Set this for GitHub Enterprise Server or GitHub Enterprise Cloud with data residency. Leave empty for github.com.",
+          "type": "url",
+          "required": false,
+          "secret": false,
+          "default": "https://api.github.com",
+          "placeholder": "https://github.example.com"
         }
       ]
     }