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.

#import <CkoMcp.h>
#import <CkoJsonObject.h>

BOOL success = NO;

CkoMcp *mcp = [[CkoMcp alloc] init];

//  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 == NO) {
    NSLog(@"%@",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.
CkoJsonObject *args = [[CkoJsonObject alloc] init];
[args UpdateString: @"query" value: @"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.
CkoJsonObject *result = [[CkoJsonObject alloc] init];
success = [mcp CallTool: @"microsoft_docs_search" arguments: args result: result];
if (success == NO) {
    NSLog(@"%@",mcp.LastErrorText);
    return;
}

result.EmitCompact = NO;
NSLog(@"%@",[result Emit]);
//  JSON parsing code for this result can be generated at Chilkat's online tool:
//  https://tools.chilkat.io/jsonParse