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.

var
success: Integer;
mcp: TChilkatMcp;
args: TChilkatJsonObject;
result: TChilkatJsonObject;

begin
success := 0;

mcp := TChilkatMcp.Create(Self);

//  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 = 0) then
  begin
    Memo1.Lines.Add(mcp.LastErrorText);
    Exit;
  end;

//  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.
args := TChilkatJsonObject.Create(Self);
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.
result := TChilkatJsonObject.Create(Self);
success := mcp.CallTool('microsoft_docs_search',args.ControlInterface,result.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(mcp.LastErrorText);
    Exit;
  end;

result.EmitCompact := 0;
Memo1.Lines.Add(result.Emit());
//  JSON parsing code for this result can be generated at Chilkat's online tool:
//  https://tools.chilkat.io/jsonParse