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.

local chilkat = require("chilkat")

local 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.
local success = mcp:connect("https://learn.microsoft.com/api/mcp")
if not success then
    print(mcp.last_error_text)
    return
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.
local args = chilkat.JsonObject.new()
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.
local result = chilkat.JsonObject.new()
success = mcp:call_tool("microsoft_docs_search", args, result)
if not success then
    print(mcp.last_error_text)
    return
end

result.emit_compact = false
print(result:emit())
-- JSON parsing code for this result can be generated at Chilkat's online tool:
-- https://tools.chilkat.io/jsonParse