LLM - ToolCallinin C

lmf2-tools.cs

/*
 * TestLfmTools.cs
 * LFM2.5-1.2B tool calling test — rewritten with the OpenAI NuGet package.
 * Ollama exposes an OpenAI-compatible endpoint, so no manual ChatML or
 * regex parsing needed.
 *
 * Requirements: .NET 8+
 *   dotnet add package OpenAI --version 2.*
 *
 * NOTE: Tool calling via the OpenAI-compatible endpoint requires the model
 * to have a tool template in its Modelfile. The community upload
 * hadad/LFM2.5-1.2B lacks one, so create a local model first:
 *
 *   ollama show hadad/LFM2.5-1.2B:Q4_K_M --modelfile > Modelfile
 *   # add TEMPLATE block (see README) then:
 *   ollama create lfm2.5-tools -f Modelfile
 *
 * Or simply swap the model name below for one that supports tools natively,
 * e.g. "qwen2.5:1.5b" or "llama3.2:1b".
 *
 * Build & run:
 *   dotnet new console -n LfmTest && cd LfmTest
 *   dotnet add package OpenAI --version 2.*
 *   cp ../TestLfmTools.cs Program.cs
 *   dotnet run
 */

using System;
using System.ClientModel;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text.Json;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using OpenAI;
using OpenAI.Chat;

await Program.Main();

// ────────────────────────────────────────────────────────────────────────────
static class Program
{
    // Ollama's OpenAI-compatible base URL
    const string BaseUrl = "http://localhost:11434/v1";
    const string Model   = "lfm2.5-tools"; // or "qwen2.5:1.5b", "llama3.2:1b", etc.

    // ── OpenAI client pointed at local Ollama ────────────────────────────────

    static readonly ChatClient Client = new OpenAIClient(
        credential: new ApiKeyCredential("ollama"),   // Ollama ignores the key
        options: new OpenAIClientOptions { Endpoint = new Uri(BaseUrl) }
    ).GetChatClient(Model);

    // ── tool definitions ─────────────────────────────────────────────────────

    static readonly ChatTool[] Tools =
    {
        ChatTool.CreateFunctionTool(
            functionName: "get_weather",
            functionDescription: "Get the current weather for a given city.",
            functionParameters: BinaryData.FromString("""
            {
                "type": "object",
                "properties": {
                    "location": {
                        "type": "string",
                        "description": "City name, e.g. 'Paris'"
                    },
                    "unit": {
                        "type": "string",
                        "enum": ["celsius", "fahrenheit"],
                        "description": "Temperature unit (default: celsius)"
                    }
                },
                "required": ["location"]
            }
            """)
        ),

        ChatTool.CreateFunctionTool(
            functionName: "calculate",
            functionDescription:
                "Evaluate a math expression. " +
                "Use standard arithmetic operators: +, -, *, /. " +
                "For percentages write '15% of 280' or '0.15 * 280'. " +
                "Do NOT pass natural language like 'fifteen percent of 280'.",
            functionParameters: BinaryData.FromString("""
            {
                "type": "object",
                "properties": {
                    "expression": {
                        "type": "string",
                        "description": "Math expression, e.g. '(3+5)*2' or '15% of 280'"
                    }
                },
                "required": ["expression"]
            }
            """)
        ),

        ChatTool.CreateFunctionTool(
            functionName: "search_contacts",
            functionDescription: "Search for a person in the contact book by name.",
            functionParameters: BinaryData.FromString("""
            {
                "type": "object",
                "properties": {
                    "name": {
                        "type": "string",
                        "description": "Full or partial name to search for"
                    }
                },
                "required": ["name"]
            }
            """)
        ),
    };

    // ── fake tool implementations ─────────────────────────────────────────────

    static string GetWeather(string location, string unit = "celsius")
    {
        var db = new Dictionary<string, (int temp, string condition, int humidity)>(StringComparer.OrdinalIgnoreCase)
        {
            ["paris"]    = (18, "Partly cloudy", 65),
            ["london"]   = (14, "Rainy",         80),
            ["tokyo"]    = (25, "Sunny",          55),
            ["new york"] = (22, "Clear",          50),
        };

        var (temp, condition, humidity) = db.TryGetValue(location, out var v)
            ? v : (20, "Unknown", 60);

        if (unit.Equals("fahrenheit", StringComparison.OrdinalIgnoreCase))
            temp = (int)Math.Round(temp * 9.0 / 5 + 32);

        return JsonSerializer.Serialize(new { temp, condition, humidity, location, unit });
    }

    static string Calculate(string expression)
    {
        try
        {
            // Normalise "15% of 280" → "(15 / 100) * 280"
            var expr = System.Text.RegularExpressions.Regex.Replace(
                expression,
                @"(\d+(?:\.\d+)?)\s*%\s*of\s*(\d+(?:\.\d+)?)",
                m => $"({m.Groups[1].Value} / 100) * {m.Groups[2].Value}",
                System.Text.RegularExpressions.RegexOptions.IgnoreCase);

            // Normalise bare "X%" → "(X/100)"
            expr = System.Text.RegularExpressions.Regex.Replace(
                expr, @"(\d+(?:\.\d+)?)\s*%", "($1/100)");

            if (expr.Any(c => !"0123456789+-*/()., ".Contains(c)))
                return JsonSerializer.Serialize(new { error = $"Invalid characters: {expr}" });

            double result = Convert.ToDouble(new DataTable().Compute(expr, null));
            return JsonSerializer.Serialize(new { expression, result = Math.Round(result, 10) });
        }
        catch (Exception ex)
        {
            return JsonSerializer.Serialize(new { error = ex.Message });
        }
    }

    static string SearchContacts(string name)
    {
        var contacts = new[]
        {
            new { name = "Alice Martin",   email = "alice@example.com",   phone = "+33 6 12 34 56 78" },
            new { name = "Bob Dupont",     email = "bob@example.com",     phone = "+33 6 98 76 54 32" },
            new { name = "Charlie Durand", email = "charlie@example.com", phone = "+33 6 55 44 33 22" },
        };

        var matches = contacts
            .Where(c => c.name.Contains(name, StringComparison.OrdinalIgnoreCase))
            .ToArray();

        return JsonSerializer.Serialize(new { query = name, results = matches, count = matches.Length });
    }

    // ── dispatch ──────────────────────────────────────────────────────────────

    static string DispatchTool(string name, string argsJson)
    {
        // Parse the JSON args the model produced
        var args = JsonNode.Parse(argsJson) as JsonObject
                   ?? new JsonObject();

        string Get(string key, string fallback = "") =>
            args[key]?.GetValue<string>() ?? fallback;

        return name switch
        {
            "get_weather"     => GetWeather(Get("location"), Get("unit", "celsius")),
            "calculate"       => Calculate(Get("expression")),
            "search_contacts" => SearchContacts(Get("name")),
            _                 => JsonSerializer.Serialize(new { error = $"Unknown tool: {name}" }),
        };
    }

    // ── agentic loop ──────────────────────────────────────────────────────────

    static async Task<string> Run(string userPrompt)
    {
        Console.WriteLine($"\n{new string('=', 60)}");
        Console.WriteLine($"USER: {userPrompt}");

        var options = new ChatCompletionOptions();
        foreach (var tool in Tools)
            options.Tools.Add(tool);

        // Start conversation
        var messages = new List<ChatMessage>
        {
            new SystemChatMessage("You are a helpful assistant."),
            new UserChatMessage(userPrompt),
        };

        for (int iter = 0; iter < 5; iter++)
        {
            ChatCompletion response = await Client.CompleteChatAsync(messages, options);

            switch (response.FinishReason)
            {
                // ── model wants to call tools ─────────────────────────────────
                case ChatFinishReason.ToolCalls:
                {
                    // Add assistant message (with tool call requests) to history
                    messages.Add(new AssistantChatMessage(response));

                    // Execute each tool call and collect results
                    var toolResults = new List<ToolChatMessage>();
                    foreach (var tc in response.ToolCalls)
                    {
                        string argsJson = tc.FunctionArguments.ToString();
                        Console.WriteLine($"  → TOOL CALL: {tc.FunctionName}({argsJson})");

                        string result = DispatchTool(tc.FunctionName, argsJson);
                        Console.WriteLine($"  ← RESULT:    {result}");

                        toolResults.Add(new ToolChatMessage(tc.Id, result));
                    }

                    // Feed all results back in one go
                    messages.AddRange(toolResults);
                    break;
                }

                // ── final answer ──────────────────────────────────────────────
                case ChatFinishReason.Stop:
                {
                    string answer = response.Content[0].Text;
                    Console.WriteLine($"ASSISTANT: {answer}");
                    return answer;
                }

                default:
                    Console.WriteLine($"  [unexpected finish reason: {response.FinishReason}]");
                    return "";
            }
        }

        return "(max iterations reached)";
    }

    // ── test prompts ──────────────────────────────────────────────────────────

    static readonly string[] TestPrompts =
    {
        "What's the weather like in Paris right now?",
        "What is (123 * 456) + 789?",
        "Find contact info for Alice.",
        "What's the weather in Tokyo in Fahrenheit, and also calculate 15% of 280.",
    };

    // ── main ──────────────────────────────────────────────────────────────────

    public static async Task Main()
    {
        Console.WriteLine($"Model : {Model}");
        Console.WriteLine($"URL   : {BaseUrl}");
        Console.WriteLine("Ensure Ollama is running: ollama serve");

        // Quick connectivity check
        try
        {
            using var http = new System.Net.Http.HttpClient { Timeout = TimeSpan.FromSeconds(3) };
            await http.GetAsync("http://localhost:11434");
        }
        catch
        {
            Console.WriteLine("\nERROR: Cannot reach Ollama at localhost:11434.");
            Console.WriteLine("Start it with: ollama serve");
            return;
        }

        int passed = 0;
        foreach (var prompt in TestPrompts)
        {
            try
            {
                string answer = await Run(prompt);
                if (!string.IsNullOrWhiteSpace(answer)) passed++;
            }
            catch (Exception ex)
            {
                Console.WriteLine($"  ERROR: {ex.Message}");
            }
        }

        Console.WriteLine($"\n{new string('=', 60)}");
        Console.WriteLine($"Done: {passed}/{TestPrompts.Length} prompts completed.");
    }
}