MCP Tools

MCP servers are external tool sources. HPD Agent connects to configured MCP servers, imports their tools, and exposes them as model-callable functions.

Configure MCP From JSON Content

using HPD.Agent;
using HPD.Agent.MCP;

var manifest = """
{
  "servers": [
    {
      "name": "local-stdio",
      "command": "dotnet",
      "arguments": ["--info"],
      "enabled": false,
      "requiresPermission": false,
      "enablecollapsing": true
    }
  ]
}
""";

var builder = new AgentBuilder()
    .WithMCPContent(manifest, new MCPOptions
    {
        FailOnServerError = true,
        ConnectionTimeout = TimeSpan.FromSeconds(5)
    });

This shape configures MCP without relying on an external paid service. A disabled server is useful for validating configuration shape without starting a process.

Stdio Servers

For stdio servers, configure:

• name
• command
• arguments
• enabled
• requiresPermission

The current stdio startup path uses the configured command and arguments.

Harness-Owned MCP Servers

A generated harness can contribute MCP server config:

using HPD.Agent;
using HPD.Agent.MCP;

public sealed class ExternalTools
{
    [MCPServer(Description = "Local MCP server", CollapseWithinToolHarness = true)]
    public MCPServerConfig LocalMcp() => new()
    {
        Name = "local-stdio",
        Command = "dotnet",
        Arguments = ["--info"],
        Enabled = false,
        RequiresPermission = false,
    };
}

The generated path registers an MCP server source for the harness. It does not turn the method itself into a model-facing function.

Boundary

MCPServerConfig contains process-isolation configuration, but the current stdio startup path does not enforce that config when creating the MCP process. Do not rely on MCP processIsolation for runtime sandboxing. Use ordinary permissions and local sandboxing around agent tools that need process control.