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.

let mcp = chilkat::Mcp::new();

// 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.
if mcp.connect("https://learn.microsoft.com/api/mcp").is_err() {
    println!("{}", mcp.last_error_text());
    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.
let args = chilkat::JsonObject::new();
let _ = args.update_string("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.
let result = chilkat::JsonObject::new();
if mcp.call_tool("microsoft_docs_search", &args, &result).is_err() {
    println!("{}", mcp.last_error_text());
    return;
}

result.set_emit_compact(false);
println!("{}", result.emit().unwrap_or_default());
// JSON parsing code for this result can be generated at Chilkat's online tool:
// https://tools.chilkat.io/jsonParse