CloudCopilot

Blazor Server chatbot that uses the GitHub Copilot SDK (CLI server mode) and the Vantage Instances MCP server to answer cloud instance pricing questions with tool-backed facts.

Prerequisites

• .NET SDK 10.0
• GitHub Copilot CLI installed and authenticated
• Access to a Vantage Instances MCP server

Install Copilot CLI

Follow GitHub's Copilot CLI install guide for your OS:

• https://docs.github.com/copilot

After install, authenticate (command depends on your CLI install):

# Example
copilot auth login
# or
gh copilot auth login

Configuration

Set the MCP server URL and optional API key via environment variables (recommended):

export VANTAGE_INSTANCES_MCP_URL="https://your-mcp-server"
export VANTAGE_INSTANCES_MCP_KEY="your-api-key"   # optional

You can also place these in configuration (appsettings.json / appsettings.Development.json):

{
  "Vantage": {
    "InstancesMcpUrl": "https://your-mcp-server",
    "InstancesMcpKey": "your-api-key"
  }
}

Run

From the repo root:

cd src

dotnet restore

dotnet run

Navigate to the app URL shown in the console. The /health endpoint returns MCP + Copilot connectivity status.

System Overview

The app configures the Copilot SDK to use Copilot CLI server mode. The agent can only call Vantage Instances MCP tools and never uses filesystem, git, or web tools.

Flow Diagram

sequenceDiagram
  autonumber
  participant U as User (Browser)
  participant UI as Blazor UI
  participant AG as CopilotAgent
  participant CP as Copilot CLI Server
  participant MCP as Vantage MCP Server

  U->>UI: Enter question
  UI->>AG: Send user message
  AG->>CP: Plan prompt + allowed tools
  CP-->>AG: Tool call plan (JSON)
  AG->>MCP: tools/call (JSON-RPC)
  MCP-->>AG: Tool result (JSON)
  AG->>CP: Follow-up with tool results
  CP-->>AG: Final structured answer (JSON)
  AG-->>UI: Rendered response + tool logs

Architecture Diagram

flowchart LR
  subgraph Client
    Browser[Browser]
  end

  subgraph Server
    Blazor[Blazor Server App]
    Agent[CopilotAgent]
    McpClient[McpClient]
    CopilotSDK[GitHub Copilot SDK]
    Health[Health Endpoint]
  end

  subgraph External
    CopilotCLI[Copilot CLI Server]
    VantageMCP[Vantage Instances MCP]
  end

  Browser --> Blazor
  Blazor --> Agent
  Agent --> CopilotSDK
  CopilotSDK --> CopilotCLI
  Agent --> McpClient
  McpClient --> VantageMCP
  Blazor --> Health

Key Components

• src/Services/CopilotAgent.cs

  • Builds the system prompt with allowed tool list and response schema.
  • Orchestrates tool calls through MCP based on Copilot output.
  • Logs prompts, tool calls, and tool responses.

• src/Services/McpClient.cs

  • JSON-RPC client with SSE-aware parsing.
  • Logs raw MCP responses for troubleshooting.

• src/Components/Pages/Home.razor

  • Chat UI, tool call panel, and raw MCP results panel.
  • Renders structured responses (message + table + comparable options).

Tool Access Policy

Only the following MCP tools are exposed to the agent:

• list_providers
• list_families(provider)
• search_instances(provider, region?, vcpus?, memoryGiB?, gpu?, family?, priceMax?, purchaseOption?, os?)
• get_pricing(provider, instanceType, region, purchaseOption, os)
• compare_instances(provider, list, region, purchaseOption, os)

Notes

• The agent never invents prices or specs; all facts must come from MCP tool calls.
• If a pricing request omits the region, the agent asks exactly one clarifying question.
• Default purchaseOption is on-demand and default os is linux when not specified.