B4X Requires Chilkat v11.6.0+

Call a Tool on an MCP Server

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.

Background. The members of the arguments object are defined by the tool's input schema, which is reported by ListTools. This example uses the public, no-authentication Microsoft Learn MCP server.

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Dim success As Boolean = False

Dim mcp As ChilkatMcp
mcp.Initialize("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 Then
    Log(mcp.LastErrorText)
    Return
End If


'  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.
Dim args As ChilkatJsonObject
args.Initialize
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.
Dim result As ChilkatJsonObject
result.Initialize
success = mcp.CallTool("microsoft_docs_search", args, result)
If success = False Then
    Log(mcp.LastErrorText)
    Return
End If


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