Add tool calling (#112)

- add tool calling to the api interface
- add a tool calling example

examples/tools/tools.ts

@@ -0,0 +1,88 @@
+import ollama from 'ollama';
+
+// Simulates an API call to get flight times
+// In a real application, this would fetch data from a live database or API
+function getFlightTimes(departure: string, arrival: string) {
+    const flights = {
+        "NYC-LAX": { departure: "08:00 AM", arrival: "11:30 AM", duration: "5h 30m" },
+        "LAX-NYC": { departure: "02:00 PM", arrival: "10:30 PM", duration: "5h 30m" },
+        "LHR-JFK": { departure: "10:00 AM", arrival: "01:00 PM", duration: "8h 00m" },
+        "JFK-LHR": { departure: "09:00 PM", arrival: "09:00 AM", duration: "7h 00m" },
+        "CDG-DXB": { departure: "11:00 AM", arrival: "08:00 PM", duration: "6h 00m" },
+        "DXB-CDG": { departure: "03:00 AM", arrival: "07:30 AM", duration: "7h 30m" }
+    };
+
+    const key = `${departure}-${arrival}`.toUpperCase();
+    return JSON.stringify(flights[key] || { error: "Flight not found" });
+}
+
+async function run(model: string) {
+    // Initialize conversation with a user query
+    let messages = [{ role: 'user', content: 'What is the flight time from New York (NYC) to Los Angeles (LAX)?' }];
+
+    // First API call: Send the query and function description to the model
+    const response = await ollama.chat({
+        model: model,
+        messages: messages,
+        tools: [
+            {
+                type: 'function',
+                function: {
+                    name: 'get_flight_times',
+                    description: 'Get the flight times between two cities',
+                    parameters: {
+                        type: 'object',
+                        properties: {
+                            departure: {
+                                type: 'string',
+                                description: 'The departure city (airport code)',
+                            },
+                            arrival: {
+                                type: 'string',
+                                description: 'The arrival city (airport code)',
+                            },
+                        },
+                        required: ['departure', 'arrival'],
+                    },
+                },
+            },
+        ],
+    })
+    // Add the model's response to the conversation history
+    messages.push(response.message);
+
+    // Check if the model decided to use the provided function
+    if (!response.message.tool_calls || response.message.tool_calls.length === 0) {
+        console.log("The model didn't use the function. Its response was:");
+        console.log(response.message.content);
+        return;
+    }
+
+    // Process function calls made by the model
+    if (response.message.tool_calls) {
+        const availableFunctions = {
+            get_flight_times: getFlightTimes,
+        };
+        for (const tool of response.message.tool_calls) {
+            const functionToCall = availableFunctions[tool.function.name];
+            const functionResponse = functionToCall(
+                tool.function.arguments.departure,
+                tool.function.arguments.arrival
+            );
+            // Add function response to the conversation
+            messages.push({
+                role: 'tool',
+                content: functionResponse,
+            });
+        }
+    }
+
+    // Second API call: Get final response from the model
+    const finalResponse = await ollama.chat({
+        model: model,
+        messages: messages,
+    });
+    console.log(finalResponse.message.content);
+}
+
+run('mistral').catch(error => console.error("An error occurred:", error));

src/interfaces.ts

@@ -62,6 +62,35 @@ export interface Message {
   role: string
   content: string
   images?: Uint8Array[] | string[]
+  tool_calls?: ToolCall[]
+}
+
+export interface ToolCall {
+  function: {
+    name: string;
+    arguments: {
+      [key: string]: any;
+    };
+  };
+}
+
+export interface Tool {
+  type: string;
+  function: {
+    name: string;
+    description: string;
+    parameters: {
+      type: string;
+      required: string[];
+      properties: {
+        [key: string]: {
+          type: string;
+          description: string;
+          enum?: string[];
+        };
+      };
+    };
+  };
 }
 
 export interface ChatRequest {
@@ -70,6 +99,7 @@ export interface ChatRequest {
   stream?: boolean
   format?: string
   keep_alive?: string | number
+  tools?: Tool[]
 
   options?: Partial<Options>
 }