Virtual Resources & Prompt Templates Tester

The Interactive Test Bench provides specialized interfaces for inspecting virtual resources and testing prompt templates exposed by backend MCP servers.

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📄 Virtual Resource Tester (ResourceTesterCard)

Use the Virtual Resource Tester to read and verify virtual file paths, database snapshots, and system diagnostic dumps:

How to Read a Virtual Resource

1. Select Server or Template: Choose a registered server from the dropdown to view its published resources.
2. Select Resource or Specify URI: Pick an item from the pre-populated resource list or type a custom virtual URI into the Resource URI field.
3. Read Resource: Click Read Resource. The gateway requests the resource, parses the payload, and displays its MIME type, payload size, and formatted content.

Supported Virtual Resource URIs

• Downstream MCP Server Resources: URIs using the namespaced virtual scheme:

  mcp://{serverId}/{path}

  Example: mcp://docker/containers/status, mcp://filesystem/shared/config.json.
• Gateway System Resources: Built-in system introspection endpoints:
  • router://status: Returns active client session counts, connection pools, and runtime uptime.
  • router://database: Returns database connection status, registered table counts, and provider types.
  • logs://recent: Retrieves the most recent in-memory log buffer.

API & cURL Invocation

curl -X POST http://localhost:8080/api/test/resources/read \
  -H "Authorization: Bearer <YOUR_APP_KEY>" \
  -H "Content-Type: application/json" \
  -d '{
    "uri": "mcp://docker/containers/status"
  }'

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💬 Prompt Template Tester (PromptTesterCard)

Use the Prompt Template Tester to evaluate dynamic prompt templates and ensure variable substitution works before AI consumption:

How to Render a Prompt Template

1. Select Server & Template: Choose the backend server and target prompt template from the dropdown menus.
2. Supply Arguments: Enter the required and optional arguments declared by the template schema.
3. Render Prompt: Click Render Prompt. MCG evaluates the template variables and displays the resulting message array (System, User, Assistant messages).

API & cURL Invocation

curl -X POST http://localhost:8080/api/test/prompts/get \
  -H "Authorization: Bearer <YOUR_APP_KEY>" \
  -H "Content-Type: application/json" \
  -d '{
    "serverId": "notes-rag",
    "promptName": "summarize_architecture",
    "arguments": {
      "topic": "Model Context Gateway Security Hardening",
      "max_length": "500"
    }
  }'