Call a Tool on an MCP Server

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Demonstrates Mcp.CallTool, which calls the MCP tools/call method for a named tool, passing a JSON arguments object and receiving the tool's result. The example calls the Microsoft Learn microsoft_docs_search tool.

Tip: Code to parse the returned JSON can be generated with Chilkat's online tool at https://tools.chilkat.io/jsonParse.

bool success = false;

Chilkat.Mcp mcp = new Chilkat.Mcp();

//  Connect to a public MCP (Model Context Protocol) server over its Streamable HTTP endpoint.  The
//  Microsoft Learn MCP server is public and requires no authentication.
success = mcp.Connect("https://learn.microsoft.com/api/mcp");
if (success == false) {
    Debug.WriteLine(mcp.LastErrorText);
    return;
}

//  Build the tool's input arguments.  The members required depend on the tool's input schema (see
//  ListTools).  Here the Microsoft Learn "microsoft_docs_search" tool takes a search query.
Chilkat.JsonObject args = new Chilkat.JsonObject();
args.UpdateString("query","How do I create an Azure storage account?");

//  Call the MCP tools/call method for the named tool.  The tool's result is placed in the result
//  JsonObject.
Chilkat.JsonObject result = new Chilkat.JsonObject();
success = mcp.CallTool("microsoft_docs_search",args,result);
if (success == false) {
    Debug.WriteLine(mcp.LastErrorText);
    return;
}

result.EmitCompact = false;
Debug.WriteLine(result.Emit());
//  JSON parsing code for this result can be generated at Chilkat's online tool:
//  https://tools.chilkat.io/jsonParse